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GHSA-9W8R-397F-PRFH

Vulnerability from github – Published: 2021-04-20 16:35 – Updated: 2024-10-14 16:12
VLAI
Summary
Infinite Loop in Pygments
Details

An infinite loop in SMLLexer in Pygments versions 1.5 to 2.7.3 may lead to denial of service when performing syntax highlighting of a Standard ML (SML) source file, as demonstrated by input that only contains the "exception" keyword.

Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
8.7 (High)
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
Show details on source website
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{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "Pygments"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "1.5"
            },
            {
              "fixed": "2.7.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2021-20270"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-835"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2021-04-12T20:58:03Z",
    "nvd_published_at": "2021-03-23T17:15:00Z",
    "severity": "HIGH"
  },
  "details": "An infinite loop in SMLLexer in Pygments versions 1.5 to 2.7.3 may lead to denial of service when performing syntax highlighting of a Standard ML (SML) source file, as demonstrated by input that only contains the \"exception\" keyword.",
  "id": "GHSA-9w8r-397f-prfh",
  "modified": "2024-10-14T16:12:14Z",
  "published": "2021-04-20T16:35:47Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-20270"
    },
    {
      "type": "WEB",
      "url": "https://github.com/pygments/pygments/commit/f91804ff4772e3ab41f46e28d370f57898700333"
    },
    {
      "type": "WEB",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=1922136"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/pygments/pygments"
    },
    {
      "type": "WEB",
      "url": "https://github.com/pypa/advisory-database/tree/main/vulns/pygments/PYSEC-2021-140.yaml"
    },
    {
      "type": "WEB",
      "url": "https://lists.debian.org/debian-lts-announce/2021/05/msg00003.html"
    },
    {
      "type": "WEB",
      "url": "https://lists.debian.org/debian-lts-announce/2021/05/msg00006.html"
    },
    {
      "type": "WEB",
      "url": "https://www.debian.org/security/2021/dsa-4889"
    },
    {
      "type": "WEB",
      "url": "https://www.oracle.com/security-alerts/cpuoct2021.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: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": "Infinite Loop in Pygments"
}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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