FKIE_CVE-2026-4691

Vulnerability from fkie_nvd - Published: 2026-03-24 13:16 - Updated: 2026-03-26 13:16
Severity ?
9.8 (Critical) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
9.8 (Critical) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Summary
Use-after-free in the CSS Parsing and Computation component. This vulnerability affects Firefox < 149, Firefox ESR < 115.34, Firefox ESR < 140.9, Thunderbird < 149, and Thunderbird < 140.9.
References
security@mozilla.orghttps://bugzilla.mozilla.org/show_bug.cgi?id=2017512Permissions Required
security@mozilla.orghttps://www.mozilla.org/security/advisories/mfsa2026-20/Vendor Advisory
security@mozilla.orghttps://www.mozilla.org/security/advisories/mfsa2026-21/Vendor Advisory
security@mozilla.orghttps://www.mozilla.org/security/advisories/mfsa2026-22/Vendor Advisory
security@mozilla.orghttps://www.mozilla.org/security/advisories/mfsa2026-23/
security@mozilla.orghttps://www.mozilla.org/security/advisories/mfsa2026-24/
Impacted products
Vendor Product Version
mozilla firefox *
mozilla firefox *
mozilla firefox *
To clipboard 

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              "criteria": "cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:*",
              "matchCriteriaId": "063BE653-69B0-4543-9A90-BC7A62C943B5",
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  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Use-after-free in the CSS Parsing and Computation component. This vulnerability affects Firefox \u003c 149, Firefox ESR \u003c 115.34, Firefox ESR \u003c 140.9, Thunderbird \u003c 149, and Thunderbird \u003c 140.9."
    },
    {
      "lang": "es",
      "value": "Uso despu\u00e9s de liberaci\u00f3n en el componente de an\u00e1lisis y computaci\u00f3n CSS. Esta vulnerabilidad afecta a Firefox \u0026lt; 149, Firefox ESR \u0026lt; 115.34, Firefox ESR \u0026lt; 140.9, Thunderbird \u0026lt; 149, y Thunderbird \u0026lt; 140.9."
    }
  ],
  "id": "CVE-2026-4691",
  "lastModified": "2026-03-26T13:16:28.790",
  "metrics": {
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          "baseSeverity": "CRITICAL",
          "confidentialityImpact": "HIGH",
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  "published": "2026-03-24T13:16:04.937",
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  "vulnStatus": "Modified",
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}


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