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BREW-MIKUTTER-CVE-2021-3537 (GHSA-286V-PCF5-25RC)

Vulnerability from osv_homebrew – Published: 2026-08-13 17:14 – Updated: 2026-08-13 17:14 – Source website
VLAI
Summary
Nokogiri Implements libxml2 version vulnerable to null pointer dereferencing
Details

A vulnerability found in libxml2 in versions before 2.9.11 shows that it did not propagate errors while parsing XML mixed content, causing a NULL dereference. If an untrusted XML document was parsed in recovery mode and post-validated, the flaw could be used to crash the application. The highest threat from this vulnerability is to system availability.

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

{
  "affected": [
    {
      "ecosystem_specific": {
        "fix": "bump",
        "range_state": "fixed",
        "resource": "nokogiri",
        "resource_purl": "pkg:gem/nokogiri@1.16.3",
        "upstream_fixed_in": "1.11.4"
      },
      "package": {
        "ecosystem": "Homebrew",
        "name": "mikutter",
        "purl": "pkg:brew/mikutter"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "5.1.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "confidence": "high",
    "source": "matched",
    "strategy": "registry",
    "upstream_evidence": [
      {
        "ecosystem": "RubyGems",
        "key": "pkg:gem/nokogiri@1.16.3",
        "name": "nokogiri",
        "resource": "nokogiri",
        "strategy": "registry",
        "subject_version": "1.16.3"
      }
    ]
  },
  "details": "A vulnerability found in libxml2 in versions before 2.9.11 shows that it did not propagate errors while parsing XML mixed content, causing a NULL dereference. If an untrusted XML document was parsed in recovery mode and post-validated, the flaw could be used to crash the application. The highest threat from this vulnerability is to system availability.",
  "id": "BREW-mikutter-CVE-2021-3537",
  "modified": "2026-08-13T17:14:10Z",
  "published": "2026-08-13T17:14:10Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-3537"
    },
    {
      "type": "WEB",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=1956522"
    },
    {
      "type": "WEB",
      "url": "https://github.com/rubysec/ruby-advisory-db/blob/master/gems/nokogiri/CVE-2021-3537.yml"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/sparklemotion/nokogiri"
    },
    {
      "type": "WEB",
      "url": "https://github.com/sparklemotion/nokogiri/blob/2edbbef95f1dc12c1ddc5ebda71b9159026245fe/CHANGELOG.md?plain=1#L722"
    },
    {
      "type": "WEB",
      "url": "https://lists.debian.org/debian-lts-announce/2021/05/msg00008.html"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/BZOMV5J4PMZAORVT64BKLV6YIZAFDGX6"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/QVM4UJ3376I6ZVOYMHBNX4GY3NIV52WV"
    },
    {
      "type": "WEB",
      "url": "https://nokogiri.org/CHANGELOG.html#1114-2021-05-14"
    },
    {
      "type": "WEB",
      "url": "https://security.gentoo.org/glsa/202107-05"
    },
    {
      "type": "WEB",
      "url": "https://security.netapp.com/advisory/ntap-20210625-0002"
    },
    {
      "type": "WEB",
      "url": "https://www.oracle.com/security-alerts/cpuapr2022.html"
    },
    {
      "type": "WEB",
      "url": "https://www.oracle.com/security-alerts/cpujul2022.html"
    },
    {
      "type": "WEB",
      "url": "https://www.oracle.com/security-alerts/cpuoct2021.html"
    }
  ],
  "schema_version": "1.7.3",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Nokogiri Implements libxml2 version vulnerable to null pointer dereferencing",
  "upstream": [
    "GHSA-286v-pcf5-25rc",
    "CVE-2021-3537"
  ]
}



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