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PYSEC-2021-141

Vulnerability from pysec - Published: 2021-03-17 13:15 - Updated: 2021-08-27 03:22
VLAI
Details

In pygments 1.1+, fixed in 2.7.4, the lexers used to parse programming languages rely heavily on regular expressions. Some of the regular expressions have exponential or cubic worst-case complexity and are vulnerable to ReDoS. By crafting malicious input, an attacker can cause a denial of service.

Impacted products
Name purl
pygments pkg:pypi/pygments
Aliases
To clipboard 

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "pygments",
        "purl": "pkg:pypi/pygments"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2e7e8c4a7b318f4032493773732754e418279a14"
            }
          ],
          "repo": "https://github.com/pygments/pygments",
          "type": "GIT"
        },
        {
          "events": [
            {
              "introduced": "1.1"
            },
            {
              "fixed": "2.7.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.1",
        "1.1.1",
        "1.2",
        "1.2.1",
        "1.2.2",
        "1.3",
        "1.3.1",
        "1.4",
        "1.5",
        "1.6",
        "1.6rc1",
        "2.0",
        "2.0.1",
        "2.0.2",
        "2.0rc1",
        "2.1",
        "2.1.1",
        "2.1.2",
        "2.1.3",
        "2.2.0",
        "2.3.0",
        "2.3.1",
        "2.4.0",
        "2.4.1",
        "2.4.2",
        "2.5.1",
        "2.5.2",
        "2.6.0",
        "2.6.1",
        "2.7.0",
        "2.7.1",
        "2.7.2",
        "2.7.3"
      ]
    }
  ],
  "aliases": [
    "CVE-2021-27291",
    "GHSA-pq64-v7f5-gqh8"
  ],
  "details": "In pygments 1.1+, fixed in 2.7.4, the lexers used to parse programming languages rely heavily on regular expressions. Some of the regular expressions have exponential or cubic worst-case complexity and are vulnerable to ReDoS. By crafting malicious input, an attacker can cause a denial of service.",
  "id": "PYSEC-2021-141",
  "modified": "2021-08-27T03:22:17.331175Z",
  "published": "2021-03-17T13:15:00Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://gist.github.com/b-c-ds/b1a2cc0c68a35c57188575eb496de5ce"
    },
    {
      "type": "FIX",
      "url": "https://github.com/pygments/pygments/commit/2e7e8c4a7b318f4032493773732754e418279a14"
    },
    {
      "type": "WEB",
      "url": "https://lists.debian.org/debian-lts-announce/2021/03/msg00024.html"
    },
    {
      "type": "ADVISORY",
      "url": "https://www.debian.org/security/2021/dsa-4878"
    },
    {
      "type": "ADVISORY",
      "url": "https://www.debian.org/security/2021/dsa-4889"
    },
    {
      "type": "WEB",
      "url": "https://lists.debian.org/debian-lts-announce/2021/05/msg00003.html"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/WSLD67LFGXOX2K5YNESSWAS4AGZIJTUQ/"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/GSJRFHALQ7E3UV4FFMFU2YQ6LUDHAI55/"
    },
    {
      "type": "WEB",
      "url": "https://lists.debian.org/debian-lts-announce/2021/05/msg00006.html"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/advisories/GHSA-pq64-v7f5-gqh8"
    }
  ]
}



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