Common Weakness Enumeration

CWE-444

Allowed

Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')

Abstraction: Base · Status: Incomplete

API response cwe.mitre.org

The product acts as an intermediary HTTP agent (such as a proxy or firewall) in the data flow between two entities such as a client and server, but it does not interpret malformed HTTP requests or responses in ways that are consistent with how the messages will be processed by those entities that are at the ultimate destination.

625 vulnerabilities reference this CWE, most recent first.

GHSA-46Q4-43PH-C6FR

Vulnerability from github – Published: 2026-07-24 22:26 – Updated: 2026-08-12 21:12
VLAI
Summary
blaze: Chunked-body trailer fields promoted into Request.headers in blaze-server (front-end header-sanitization bypass)
Details

Summary

blaze-server can merge HTTP/1.1 chunked-body trailer fields into Request.headers. Because trailer fields are attacker-controlled, an unauthenticated remote client can inject arbitrary header names/values (e.g. X-Forwarded-For, internal-auth headers) that a fronting proxy sanitized from the request-header section, bypassing header-based trust decisions in the application.

### Impact Any http4s application using BlazeServerBuilder over HTTP/1.1 whose routes or middleware trust proxy-set headers (e.g., X-Forwarded-For, X-Real-IP, X-Forwarded-Host, org-internal auth headers) is affected. Where a fronting proxy strips/normalizes those headers but forwards chunked bodies with trailers intact, an attacker can spoof client IP for allow-lists/rate-limits/audit, forge the https scheme, or inject internal-auth headers. A promoted Connection: close trailer is also honored, allowing attacker-controlled termination of pooled backend connections.

### Workarounds Deploy behind a proxy that removes trailer fields (or rejects requests that use trailers) before forwarding; until patched, avoid trust decisions based on headers that a proxy is relied upon to sanitize.

Severity
7.4 (High)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
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{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 0.23.17"
      },
      "package": {
        "ecosystem": "Maven",
        "name": "org.http4s:blaze-http_2.13"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.23.18"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 0.23.17"
      },
      "package": {
        "ecosystem": "Maven",
        "name": "org.http4s:blaze-http_2.12"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.23.18"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 0.23.17"
      },
      "package": {
        "ecosystem": "Maven",
        "name": "org.http4s:blaze-http_3"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.23.18"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Maven",
        "name": "org.http4s:blaze-http_3"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "1.0.0-M1"
            },
            {
              "fixed": "1.0.0-M42"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 1.0.0-M41"
      },
      "package": {
        "ecosystem": "Maven",
        "name": "org.http4s:blaze-http_2.13"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "1.0.0-M1"
            },
            {
              "fixed": "1.0.0-M42"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-73495"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-444"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-07-24T22:26:48Z",
    "nvd_published_at": null,
    "severity": "HIGH"
  },
  "details": "### Summary\n  blaze-server can merge HTTP/1.1 chunked-body trailer fields into `Request.headers`. Because trailer fields are attacker-controlled, an unauthenticated remote client can inject arbitrary header names/values (e.g. `X-Forwarded-For`, internal-auth headers) that a fronting proxy sanitized from the request-header section, bypassing header-based trust decisions in the application.\n\n  ### Impact\n  Any http4s application using `BlazeServerBuilder` over HTTP/1.1 whose routes or middleware trust proxy-set headers (e.g., `X-Forwarded-For`, `X-Real-IP`, `X-Forwarded-Host`, org-internal auth headers) is affected. Where a fronting proxy strips/normalizes those headers but forwards chunked bodies with trailers intact, an attacker can spoof client IP for allow-lists/rate-limits/audit, forge the `https` scheme, or inject internal-auth headers. A promoted `Connection: close` trailer is also honored, allowing attacker-controlled termination of pooled backend connections.\n\n  ### Workarounds\n  Deploy behind a proxy that removes trailer fields (or rejects requests that use trailers) before forwarding; until patched, avoid trust decisions based on headers that a proxy is relied upon to sanitize.",
  "id": "GHSA-46q4-43ph-c6fr",
  "modified": "2026-08-12T21:12:00Z",
  "published": "2026-07-24T22:26:48Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/http4s/blaze/security/advisories/GHSA-46q4-43ph-c6fr"
    },
    {
      "type": "WEB",
      "url": "https://github.com/http4s/blaze/commit/ef3e666c146cfc16cb6603f1fc3c464daab4a24f"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/http4s/blaze"
    },
    {
      "type": "WEB",
      "url": "https://github.com/http4s/blaze/releases/tag/v0.23.18"
    },
    {
      "type": "WEB",
      "url": "https://github.com/http4s/blaze/releases/tag/v1.0.0-M42"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "blaze: Chunked-body trailer fields promoted into Request.headers in blaze-server (front-end header-sanitization bypass)"
}

GHSA-478M-XRV3-7R93

Vulnerability from github – Published: 2022-05-24 17:14 – Updated: 2024-04-04 02:49
VLAI
Details

An issue was discovered in OpenResty before 1.15.8.4. ngx_http_lua_subrequest.c allows HTTP request smuggling, as demonstrated by the ngx.location.capture API.

Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Show details on source website
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{
  "affected": [],
  "aliases": [
    "CVE-2020-11724"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-444"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2020-04-12T21:15:00Z",
    "severity": "HIGH"
  },
  "details": "An issue was discovered in OpenResty before 1.15.8.4. ngx_http_lua_subrequest.c allows HTTP request smuggling, as demonstrated by the ngx.location.capture API.",
  "id": "GHSA-478m-xrv3-7r93",
  "modified": "2024-04-04T02:49:48Z",
  "published": "2022-05-24T17:14:03Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2020-11724"
    },
    {
      "type": "WEB",
      "url": "https://github.com/openresty/lua-nginx-module/commit/9ab38e8ee35fc08a57636b1b6190dca70b0076fa"
    },
    {
      "type": "WEB",
      "url": "https://github.com/openresty/openresty/blob/4e8b4c395f842a078e429c80dd063b2323999957/patches/ngx_http_lua-0.10.15-fix_location_capture_content_length_chunked.patch"
    },
    {
      "type": "WEB",
      "url": "https://lists.debian.org/debian-lts-announce/2020/07/msg00014.html"
    },
    {
      "type": "WEB",
      "url": "https://security.netapp.com/advisory/ntap-20210129-0002"
    },
    {
      "type": "WEB",
      "url": "https://www.debian.org/security/2020/dsa-4750"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-48W2-RM65-62XX

Vulnerability from github – Published: 2021-10-12 17:53 – Updated: 2025-05-27 15:16
VLAI
Summary
Puma with proxy which forwards LF characters as line endings could allow HTTP request smuggling
Details

Impact

Prior to puma version 5.5.0, using puma with a proxy which forwards LF characters as line endings could allow HTTP request smuggling. A client could smuggle a request through a proxy, causing the proxy to send a response back to another unknown client.

This behavior (forwarding LF characters as line endings) is very uncommon amongst proxy servers, so we have graded the impact here as "low". Puma is only aware of a single proxy server which has this behavior.

If the proxy uses persistent connections and the client adds another request in via HTTP pipelining, the proxy may mistake it as the first request's body. Puma, however, would see it as two requests, and when processing the second request, send back a response that the proxy does not expect. If the proxy has reused the persistent connection to Puma to send another request for a different client, the second response from the first client will be sent to the second client.

Patches

This vulnerability was patched in Puma 5.5.1 and 4.3.9.

Workarounds

This vulnerability only affects Puma installations without any proxy in front.

Use a proxy which does not forward LF characters as line endings.

Proxies which do not forward LF characters as line endings:

  • Nginx
  • Apache (>2.4.25)
  • Haproxy
  • Caddy
  • Traefik

Possible Breakage

If you are dealing with legacy clients that want to send LF as a line ending in an HTTP header, this will cause those clients to receive a 400 error.

References

For more information

If you have any questions or comments about this advisory:

Severity
3.7 (Low)
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:L/I:L/A:N
Show details on source website
To clipboard 

{
  "affected": [
    {
      "package": {
        "ecosystem": "RubyGems",
        "name": "puma"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "5.0.0"
            },
            {
              "fixed": "5.5.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "RubyGems",
        "name": "puma"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.3.9"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2021-41136"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-444"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2021-10-12T17:06:36Z",
    "nvd_published_at": "2021-10-12T16:15:00Z",
    "severity": "LOW"
  },
  "details": "### Impact\n\nPrior to `puma` version 5.5.0, using `puma` with a proxy which forwards LF characters as line endings could allow HTTP request smuggling. A client could smuggle a request through a proxy, causing the proxy to send a response back to another unknown client.\n\nThis behavior (forwarding LF characters as line endings) is very uncommon amongst proxy servers, so we have graded the impact here as \"low\". Puma is only aware of a single proxy server which has this behavior.\n\nIf the proxy uses persistent connections and the client adds another request in via HTTP pipelining, the proxy may mistake it as the first request\u0027s body. Puma, however, would see it as two requests, and when processing the second request, send back a response that the proxy does not expect. If the proxy has reused the persistent connection to Puma to send another request for a different client, the second response from the first client will be sent to the second client.\n\n### Patches\n\nThis vulnerability was patched in Puma 5.5.1 and 4.3.9.\n\n### Workarounds\n\nThis vulnerability only affects Puma installations without any proxy in front.\n\nUse a proxy which does not forward LF characters as line endings.\n\nProxies which do not forward LF characters as line endings:\n\n* Nginx\n* Apache (\u003e2.4.25)\n* Haproxy\n* Caddy\n* Traefik\n\n### Possible Breakage\n\nIf you are [dealing with legacy clients that want to send `LF` as a line ending](https://stackoverflow.com/questions/43574428/have-apache-accept-lf-vs-crlf-in-request-headers) in an HTTP header, this will cause those clients to receive a `400` error.\n\n### References\n\n* [HTTP Request Smuggling](https://portswigger.net/web-security/request-smuggling)\n\n### For more information\n\nIf you have any questions or comments about this advisory:\n\n* Open an issue in [Puma](https://github.com/puma/puma)\n* See our [security policy](https://github.com/puma/puma/security/policy)",
  "id": "GHSA-48w2-rm65-62xx",
  "modified": "2025-05-27T15:16:14Z",
  "published": "2021-10-12T17:53:00Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/puma/puma/security/advisories/GHSA-48w2-rm65-62xx"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-41136"
    },
    {
      "type": "WEB",
      "url": "https://github.com/puma/puma/commit/436c71807f00e07070902a03f79fd3e130eb6b18"
    },
    {
      "type": "WEB",
      "url": "https://github.com/puma/puma/commit/acdc3ae571dfae0e045cf09a295280127db65c7f"
    },
    {
      "type": "WEB",
      "url": "https://github.com/puma/puma/commit/fb6ad8f8013ab5cdbb2f444cbfabd0b4fde71139"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/puma/puma"
    },
    {
      "type": "WEB",
      "url": "https://github.com/puma/puma/releases/tag/v4.3.9"
    },
    {
      "type": "WEB",
      "url": "https://github.com/puma/puma/releases/tag/v5.5.1"
    },
    {
      "type": "WEB",
      "url": "https://github.com/rubysec/ruby-advisory-db/blob/master/gems/puma/CVE-2021-41136.yml"
    },
    {
      "type": "WEB",
      "url": "https://lists.debian.org/debian-lts-announce/2022/08/msg00015.html"
    },
    {
      "type": "WEB",
      "url": "https://security.gentoo.org/glsa/202208-28"
    },
    {
      "type": "WEB",
      "url": "https://www.debian.org/security/2022/dsa-5146"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:L/I:L/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Puma with proxy which forwards LF characters as line endings could allow HTTP request smuggling"
}

GHSA-49CF-MFFG-JJ22

Vulnerability from github – Published: 2024-09-08 12:32 – Updated: 2024-09-08 12:32
VLAI
Details

Loway - CWE-444: Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')

Severity
4.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
Show details on source website
To clipboard 

{
  "affected": [],
  "aliases": [
    "CVE-2024-42342"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-444"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2024-09-08T12:15:10Z",
    "severity": "MODERATE"
  },
  "details": "Loway -  CWE-444: Inconsistent Interpretation of HTTP Requests (\u0027HTTP Request/Response Smuggling\u0027)",
  "id": "GHSA-49cf-mffg-jj22",
  "modified": "2024-09-08T12:32:45Z",
  "published": "2024-09-08T12:32:45Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-42342"
    },
    {
      "type": "WEB",
      "url": "https://www.gov.il/en/Departments/faq/cve_advisories"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-4C5F-9MJ4-M247

Vulnerability from github – Published: 2026-01-05 15:07 – Updated: 2026-01-05 15:07
VLAI
Summary
flagd: Multiple Go Runtime CVEs Impact Security and Availability
Details

Summary

In 2025, several vulnerabilities in the Go Standard Library were disclosed, impacting Go-based applications like flagd (the evaluation engine for OpenFeature). These CVEs primarily focus on Denial of Service (DoS) through resource exhaustion and Race Conditions in database handling.

CVE ID Impacted Package Severity Description & Impact on flagd
CVE-2025-47907 database/sql 7.0 (High) Race Condition: Canceling a query during a Scan call can return data from the wrong query. Critical if flagd uses SQL-based sync providers (e.g., Postgres), potentially leading to incorrect flag configurations.
CVE-2025-61725 net/mail 7.5 (High) DoS: Inefficient complexity in ParseAddress. Attackers can provide crafted email strings with large domain literals to exhaust CPU if flagd parses email-formatted metadata.
CVE-2025-61723 encoding/pem 7.5 (High) DoS: Quadratic complexity when parsing invalid PEM inputs. Relevant if flagd loads TLS certificates or keys via PEM files from untrusted sources.
CVE-2025-61729 crypto/x509 7.5 (High) Resource Exhaustion: HostnameError.Error() lacks string concatenation limits. A malicious TLS certificate with thousands of hostnames could crash flagd during connection handshakes.
CVE-2025-58188 net/http Medium Request Smuggling: Improper header handling in HTTP/1.1. Could allow attackers to bypass security filters positioned in front of flagd sync or evaluation APIs.
CVE-2025-58187 archive/zip Medium DoS: Improper validation of malformed ZIP archives. Impacts flagd if configured to fetch and unpack zipped configuration bundles from remote providers.
Show details on source website
To clipboard 

{
  "affected": [
    {
      "package": {
        "ecosystem": "Go",
        "name": "github.com/open-feature/flagd/core"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.13.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Go",
        "name": "github.com/open-feature/flagd/flagd-proxy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.8.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Go",
        "name": "github.com/open-feature/flagd/flagd"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.13.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [],
  "database_specific": {
    "cwe_ids": [
      "CWE-20",
      "CWE-362",
      "CWE-400",
      "CWE-407",
      "CWE-444",
      "CWE-770"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-01-05T15:07:05Z",
    "nvd_published_at": null,
    "severity": "HIGH"
  },
  "details": "### Summary\nIn 2025, several vulnerabilities in the Go Standard Library were disclosed, impacting Go-based applications like flagd (the evaluation engine for OpenFeature). These CVEs primarily focus on Denial of Service (DoS) through resource exhaustion and Race Conditions in database handling. \n\n| CVE ID | Impacted Package | Severity | Description \u0026 Impact on flagd |\n| -- | -- | -- | -- |\n| CVE-2025-47907 | database/sql | 7.0 (High) | Race Condition:  Canceling a query during a Scan call can return data from the wrong query. Critical if flagd uses SQL-based sync providers (e.g., Postgres), potentially leading to incorrect flag configurations. |\n| CVE-2025-61725 | net/mail | 7.5 (High) | DoS: Inefficient complexity in ParseAddress.  Attackers can provide crafted email strings with large domain literals to exhaust CPU if flagd parses email-formatted metadata. |\n| CVE-2025-61723 | encoding/pem | 7.5 (High) | DoS: Quadratic complexity when parsing invalid PEM inputs. Relevant if flagd loads TLS certificates or keys via PEM files from untrusted sources. |\n| CVE-2025-61729 | crypto/x509 | 7.5 (High) | Resource Exhaustion: HostnameError.Error() lacks string concatenation limits. A malicious TLS certificate with thousands of hostnames could crash flagd during connection handshakes. |\n| CVE-2025-58188 | net/http | Medium | Request Smuggling: Improper header handling in HTTP/1.1. Could allow attackers to bypass security filters positioned in front of flagd sync or evaluation APIs. |\n| CVE-2025-58187 | archive/zip | Medium | DoS:  Improper validation of malformed ZIP archives.  Impacts flagd if configured to fetch and unpack zipped configuration bundles from remote providers. |",
  "id": "GHSA-4c5f-9mj4-m247",
  "modified": "2026-01-05T15:07:46Z",
  "published": "2026-01-05T15:07:05Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/open-feature/flagd/security/advisories/GHSA-4c5f-9mj4-m247"
    },
    {
      "type": "WEB",
      "url": "https://github.com/open-feature/flagd/pull/1840"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/open-feature/flagd"
    },
    {
      "type": "WEB",
      "url": "https://github.com/open-feature/flagd/releases/tag/core%2Fv0.13.1"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [],
  "summary": "flagd: Multiple Go Runtime CVEs Impact Security and Availability"
}

GHSA-4F7P-27JC-3C36

Vulnerability from github – Published: 2022-03-18 19:00 – Updated: 2024-11-19 16:04
VLAI
Summary
HTTP Request Smuggling in waitress
Details

Impact

When using Waitress behind a proxy that does not properly validate the incoming HTTP request matches the RFC7230 standard, Waitress and the frontend proxy may disagree on where one request starts and where it ends.

This would allow requests to be smuggled via the front-end proxy to waitress and later behavior.

There are two classes of vulnerability that may lead to request smuggling that are addressed by this advisory:

  • The use of Python's int() to parse strings into integers, leading to +10 to be parsed as 10, or 0x01 to be parsed as 1, where as the standard specifies that the string should contain only digits or hex digits.
  • Waitress does not support chunk extensions, however it was discarding them without validating that they did not contain illegal characters

Patches

This has been fixed in Waitress 2.1.1

Workarounds

When deploying a proxy in front of waitress, turning on any and all functionality to make sure that the request matches the RFC7230 standard. Certain proxy servers may not have this functionality though and users are encouraged to upgrade to the latest version of waitress instead.

References

  • https://portswigger.net/research/http-desync-attacks-request-smuggling-reborn

For more information

If you have any questions or comments about this advisory: * Open an issue in the Github issue tracker (if not security related/sensitive) * Email us at pylons-project-security@googlegroups.com (If security related or sensitive)

Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
8.7 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
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{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "waitress"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.1.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2022-24761"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-444"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2022-03-18T19:00:59Z",
    "nvd_published_at": "2022-03-17T13:15:00Z",
    "severity": "HIGH"
  },
  "details": "### Impact\n\nWhen using Waitress behind a proxy that does not properly validate the incoming HTTP request matches the RFC7230 standard, Waitress and the frontend proxy may disagree on where one request starts and where it ends.\n\nThis would allow requests to be smuggled via the front-end proxy to waitress and later behavior.\n\nThere are two classes of vulnerability that may lead to request smuggling that are addressed by this advisory:\n\n- The use of Python\u0027s `int()` to parse strings into integers, leading to `+10` to be parsed as `10`, or `0x01` to be parsed as `1`, where as the standard specifies that the string should contain only digits or hex digits.\n- Waitress does not support chunk extensions, however it was discarding them without validating that they did not contain illegal characters\n\n### Patches\n\nThis has been fixed in Waitress 2.1.1\n\n### Workarounds\n\nWhen deploying a proxy in front of waitress, turning on any and all functionality to make sure that the request matches the RFC7230 standard. Certain proxy servers may not have this functionality though and users are encouraged to upgrade to the latest version of waitress instead.\n\n### References\n\n- https://portswigger.net/research/http-desync-attacks-request-smuggling-reborn\n\n### For more information\n\nIf you have any questions or comments about this advisory:\n* Open an issue in [the Github issue tracker](https://github.com/Pylons/waitress/issues) (if not security related/sensitive)\n* Email us at [pylons-project-security@googlegroups.com](mailto:pylons-project-security@googlegroups.com) (If security related or sensitive)\n",
  "id": "GHSA-4f7p-27jc-3c36",
  "modified": "2024-11-19T16:04:18Z",
  "published": "2022-03-18T19:00:59Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/Pylons/waitress/security/advisories/GHSA-4f7p-27jc-3c36"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2022-24761"
    },
    {
      "type": "WEB",
      "url": "https://github.com/Pylons/waitress/commit/9e0b8c801e4d505c2ffc91b891af4ba48af715e0"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/Pylons/waitress"
    },
    {
      "type": "WEB",
      "url": "https://github.com/Pylons/waitress/releases/tag/v2.1.1"
    },
    {
      "type": "WEB",
      "url": "https://github.com/pypa/advisory-database/tree/main/vulns/waitress/PYSEC-2022-169.yaml"
    },
    {
      "type": "WEB",
      "url": "https://lists.debian.org/debian-lts-announce/2022/05/msg00011.html"
    },
    {
      "type": "WEB",
      "url": "https://www.debian.org/security/2022/dsa-5138"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "HTTP Request Smuggling in waitress"
}

GHSA-4GXJ-RHQQ-64R3

Vulnerability from github – Published: 2026-08-28 21:31 – Updated: 2026-09-01 21:31
VLAI
Details

An issue in BitChat for iOS v1.15.0 allows a remote attacker to cause a denial of service via an unauthenticated MESSAGE packet into the mesh gossip cache

Severity
6.5 (Medium)
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Show details on source website
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{
  "affected": [],
  "aliases": [
    "CVE-2026-51376"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-444"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-08-28T20:18:04Z",
    "severity": "MODERATE"
  },
  "details": "An issue in BitChat for iOS v1.15.0 allows a remote attacker to cause a denial of service via an unauthenticated MESSAGE packet into the mesh gossip cache",
  "id": "GHSA-4gxj-rhqq-64r3",
  "modified": "2026-09-01T21:31:27Z",
  "published": "2026-08-28T21:31:13Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-51376"
    },
    {
      "type": "WEB",
      "url": "https://github.com/permissionlesstech/bitchat/pull/998"
    },
    {
      "type": "WEB",
      "url": "https://barghest.asia/blog/bitchat-cache-poisoning"
    },
    {
      "type": "WEB",
      "url": "https://github.com/BARGHEST-ngo/PoC_Bitchat1.15.0_iOS-BLEcache-poisoning"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-4HRQ-XFJW-8G7P

Vulnerability from github – Published: 2022-02-10 00:00 – Updated: 2026-07-05 03:30
VLAI
Details

An HTTP smuggling attack in the web application of D-Link DIR-X1860 before v1.10WWB09_Beta allows a remote unauthenticated attacker to DoS the web application via sending a specific HTTP packet.

Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Show details on source website
To clipboard 

{
  "affected": [],
  "aliases": [
    "CVE-2021-41442"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-444"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2022-02-09T20:15:00Z",
    "severity": "HIGH"
  },
  "details": "An HTTP smuggling attack in the web application of D-Link DIR-X1860 before v1.10WWB09_Beta allows a remote unauthenticated attacker to DoS the web application via sending a specific HTTP packet.",
  "id": "GHSA-4hrq-xfjw-8g7p",
  "modified": "2026-07-05T03:30:45Z",
  "published": "2022-02-10T00:00:20Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-41442"
    },
    {
      "type": "WEB",
      "url": "https://supportannouncement.us.dlink.com/announcement/publication.aspx?name=SAP10283"
    },
    {
      "type": "WEB",
      "url": "https://www.dlink.com/en/security-bulletin"
    },
    {
      "type": "WEB",
      "url": "http://d-link.com"
    },
    {
      "type": "WEB",
      "url": "http://dir-x1860.com"
    }
  ],
  "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:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-4HV7-632M-J4JC

Vulnerability from github – Published: 2022-05-24 17:34 – Updated: 2022-05-24 17:34
VLAI
Details

In JetBrains Ktor before 1.4.1, HTTP request smuggling was possible.

Show details on source website
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{
  "affected": [],
  "aliases": [
    "CVE-2020-26129"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-444"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2020-11-16T16:15:00Z",
    "severity": "MODERATE"
  },
  "details": "In JetBrains Ktor before 1.4.1, HTTP request smuggling was possible.",
  "id": "GHSA-4hv7-632m-j4jc",
  "modified": "2022-05-24T17:34:16Z",
  "published": "2022-05-24T17:34:16Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2020-26129"
    },
    {
      "type": "WEB",
      "url": "https://blog.jetbrains.com"
    },
    {
      "type": "WEB",
      "url": "https://blog.jetbrains.com/2020/11/16/jetbrains-security-bulletin-q3-2020"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

GHSA-4MP9-239F-G9HG

Vulnerability from github – Published: 2026-07-22 21:48 – Updated: 2026-07-22 21:48
VLAI
Summary
Netty: WebSockets V07/V08 handshaker missing Connection/Upgrade validation
Details

Summary

An attacker can force WebSocket upgrade via the lax V07 (or V08) handshaker by sending Sec-WebSocket-Version: 7 and omitting Connection: Upgrade / Upgrade: websocket headers, completing a protocol switch that a proxy would not recognize as an Upgrade request and enabling HTTP request smuggling / protocol-confusion attacks.

Severity
6.3 (Medium)
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N
Show details on source website
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{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 4.2.15.Final"
      },
      "package": {
        "ecosystem": "Maven",
        "name": "io.netty:netty-codec-http"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "4.2.0.Final"
            },
            {
              "fixed": "4.2.16.Final"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Maven",
        "name": "io.netty:netty-codec-http"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.1.136.Final"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-59898"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-444"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-07-22T21:48:59Z",
    "nvd_published_at": null,
    "severity": "MODERATE"
  },
  "details": "## Summary\nAn attacker can force WebSocket upgrade via the lax V07 (or V08) handshaker by sending `Sec-WebSocket-Version: 7` and omitting `Connection: Upgrade` / `Upgrade: websocket` headers, completing a protocol switch that a proxy would not recognize as an Upgrade request and enabling HTTP request smuggling / protocol-confusion attacks.",
  "id": "GHSA-4mp9-239f-g9hg",
  "modified": "2026-07-22T21:48:59Z",
  "published": "2026-07-22T21:48:59Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/netty/netty/security/advisories/GHSA-4mp9-239f-g9hg"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/netty/netty"
    },
    {
      "type": "WEB",
      "url": "https://github.com/netty/netty/releases/tag/netty-4.1.136.Final"
    },
    {
      "type": "WEB",
      "url": "https://github.com/netty/netty/releases/tag/netty-4.2.16.Final"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Netty: WebSockets V07/V08 handshaker missing Connection/Upgrade validation"
}
Mitigation
Implementation

Use a web server that employs a strict HTTP parsing procedure, such as Apache [REF-433].

Mitigation
Implementation

Use only SSL communication.

Mitigation
Implementation

Terminate the client session after each request.

Mitigation
System Configuration

Turn all pages to non-cacheable.

CAPEC-273: HTTP Response Smuggling

An adversary manipulates and injects malicious content in the form of secret unauthorized HTTP responses, into a single HTTP response from a vulnerable or compromised back-end HTTP agent (e.g., server).

See CanPrecede relationships for possible consequences.

CAPEC-33: HTTP Request Smuggling

An adversary abuses the flexibility and discrepancies in the parsing and interpretation of HTTP Request messages using various HTTP headers, request-line and body parameters as well as message sizes (denoted by the end of message signaled by a given HTTP header) by different intermediary HTTP agents (e.g., load balancer, reverse proxy, web caching proxies, application firewalls, etc.) to secretly send unauthorized and malicious HTTP requests to a back-end HTTP agent (e.g., web server).

See CanPrecede relationships for possible consequences.

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