BREW-MDLESS-CVE-2020-26298 (GHSA-Q3WR-QW3G-3P4H)

Vulnerability from osv_homebrew – Published: 2026-08-13 17:13 – Updated: 2026-08-13 17:13 – Source website
VLAI
Summary
Injection/XSS in Redcarpet
Details

Redcarpet is a Ruby library for Markdown processing. In Redcarpet before version 3.5.1, there is an injection vulnerability which can enable a cross-site scripting attack. In affected versions no HTML escaping was being performed when processing quotes. This applies even when the :escape_html option was being used. This is fixed in version 3.5.1 by the referenced commit.

Severity
6.8 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:N/I:H/A:N
References
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {
        "fix": "bump",
        "range_state": "fixed",
        "resource": "redcarpet",
        "resource_purl": "pkg:gem/redcarpet@3.6.1",
        "upstream_fixed_in": "3.5.1"
      },
      "package": {
        "ecosystem": "Homebrew",
        "name": "mdless",
        "purl": "pkg:brew/mdless"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "2.1.68"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "confidence": "high",
    "source": "matched",
    "strategy": "registry",
    "upstream_evidence": [
      {
        "ecosystem": "RubyGems",
        "key": "pkg:gem/redcarpet@3.6.1",
        "name": "redcarpet",
        "resource": "redcarpet",
        "strategy": "registry",
        "subject_version": "3.6.1"
      }
    ]
  },
  "details": "Redcarpet is a Ruby library for Markdown processing. In Redcarpet before version 3.5.1, there is an injection vulnerability which can enable a cross-site scripting attack. In affected versions no HTML escaping was being performed when processing quotes. This applies even when the `:escape_html` option was being used.  This is fixed in version 3.5.1 by the referenced commit.",
  "id": "BREW-mdless-CVE-2020-26298",
  "modified": "2026-08-13T17:13:14Z",
  "published": "2026-08-13T17:13:14Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2020-26298"
    },
    {
      "type": "WEB",
      "url": "https://github.com/vmg/redcarpet/commit/a699c82292b17c8e6a62e1914d5eccc252272793"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/advisories/GHSA-q3wr-qw3g-3p4h"
    },
    {
      "type": "WEB",
      "url": "https://github.com/rubysec/ruby-advisory-db/blob/master/gems/redcarpet/CVE-2020-26298.yml"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/vmg/redcarpet"
    },
    {
      "type": "WEB",
      "url": "https://github.com/vmg/redcarpet/blob/master/CHANGELOG.md#version-351-security"
    },
    {
      "type": "WEB",
      "url": "https://lists.debian.org/debian-lts-announce/2021/01/msg00014.html"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/BFMYDIONVWATY7EB6EARDVXT47AYCRNM"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/FNO4ZZUPGAEUXKQL4G2HRIH7CUZKPCT6"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/PXNNWHHAPREDM3XJDACYRTK7DBMUONBI"
    },
    {
      "type": "WEB",
      "url": "https://rubygems.org/gems/redcarpet"
    },
    {
      "type": "WEB",
      "url": "https://www.debian.org/security/2021/dsa-4831"
    }
  ],
  "schema_version": "1.7.3",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:N/I:H/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Injection/XSS in Redcarpet",
  "upstream": [
    "GHSA-q3wr-qw3g-3p4h",
    "CVE-2020-26298"
  ]
}



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