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GHSA-55XV-F85C-248Q

Vulnerability from github – Published: 2021-12-17 19:59 – Updated: 2022-01-04 19:52
VLAI
Summary
Regular Expression Denial of Service (ReDoS) in jsx-slack
Details

jsx-slack v4.5.1 and earlier versions are vulnerable to a regular expression denial-of-service (ReDoS) attack.

Impact

If attacker can put a lot of JSX elements into <blockquote> tag, an internal regular expression for escaping characters may consume an excessive amount of computing resources.

/** @jsxImportSource jsx-slack */
import { Section } from 'jsx-slack'

console.log(
  <Section>
    <blockquote>
      {[...Array(40)].map((_, i) => (
        <p>{i + 1}</p>
      ))}
    </blockquote>
  </Section>
)

Patches

See also: https://github.com/yhatt/jsx-slack/security/advisories/GHSA-hp68-xhvj-x6j6

jsx-slack v4.5.2 has updated regular expressions to prevent catastrophic backtracking.

jsx-slack v4.5.1 also had patched a workaround. It has no problems to contents with ASCII characters, but still vulnerable to contents with multibyte characters. (https://github.com/yhatt/jsx-slack/commit/36e4a10405e4c7745333e245fcc5029c02c7065d)

References

  • https://nvd.nist.gov/vuln/detail/CVE-2021-43838
  • https://github.com/yhatt/jsx-slack/commit/36e4a10405e4c7745333e245fcc5029c02c7065d

Credits

Thanks to @hieki for finding out this vulnerability.

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

{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "jsx-slack"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.5.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2021-43838"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-1333",
      "CWE-400"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2021-12-17T19:33:23Z",
    "nvd_published_at": "2021-12-17T19:15:00Z",
    "severity": "LOW"
  },
  "details": "jsx-slack v4.5.1 and earlier versions are vulnerable to a regular expression denial-of-service (ReDoS) attack. \n\n### Impact\n\nIf attacker can put a lot of JSX elements into `\u003cblockquote\u003e` tag, an internal regular expression for escaping characters may consume an excessive amount of computing resources.\n\n```javascript\n/** @jsxImportSource jsx-slack */\nimport { Section } from \u0027jsx-slack\u0027\n\nconsole.log(\n  \u003cSection\u003e\n    \u003cblockquote\u003e\n      {[...Array(40)].map((_, i) =\u003e (\n        \u003cp\u003e{i + 1}\u003c/p\u003e\n      ))}\n    \u003c/blockquote\u003e\n  \u003c/Section\u003e\n)\n```\n\n### Patches\n\n_See also: https://github.com/yhatt/jsx-slack/security/advisories/GHSA-hp68-xhvj-x6j6_\n\njsx-slack v4.5.2 has updated regular expressions to prevent catastrophic backtracking.\n\njsx-slack v4.5.1 also had patched a workaround. It has no problems to contents with ASCII characters, but _still vulnerable to contents with multibyte characters_. (https://github.com/yhatt/jsx-slack/commit/36e4a10405e4c7745333e245fcc5029c02c7065d)\n\n### References\n\n- https://nvd.nist.gov/vuln/detail/CVE-2021-43838\n- https://github.com/yhatt/jsx-slack/commit/36e4a10405e4c7745333e245fcc5029c02c7065d\n\n### Credits\n\nThanks to @hieki for finding out this vulnerability.",
  "id": "GHSA-55xv-f85c-248q",
  "modified": "2022-01-04T19:52:06Z",
  "published": "2021-12-17T19:59:02Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/yhatt/jsx-slack/security/advisories/GHSA-55xv-f85c-248q"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-43838"
    },
    {
      "type": "WEB",
      "url": "https://github.com/yhatt/jsx-slack/commit/36e4a10405e4c7745333e245fcc5029c02c7065d"
    },
    {
      "type": "WEB",
      "url": "https://github.com/yhatt/jsx-slack"
    }
  ],
  "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:L",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Regular Expression Denial of Service (ReDoS) in jsx-slack"
}



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