GHSA-H6R3-P5GV-5QGC

Vulnerability from github – Published: 2026-03-24 15:30 – Updated: 2026-06-30 03:35
VLAI
Details

Memory safety bugs present in Firefox ESR 140.8, Thunderbird ESR 140.8, Firefox 148 and Thunderbird 148. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability affects Firefox < 149 and Firefox ESR < 140.9.

Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
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{
  "affected": [],
  "aliases": [
    "CVE-2026-4720"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-120"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-03-24T13:16:07Z",
    "severity": "CRITICAL"
  },
  "details": "Memory safety bugs present in Firefox ESR 140.8, Thunderbird ESR 140.8, Firefox 148 and Thunderbird 148. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability affects Firefox \u003c 149 and Firefox ESR \u003c 140.9.",
  "id": "GHSA-h6r3-p5gv-5qgc",
  "modified": "2026-06-30T03:35:59Z",
  "published": "2026-03-24T15:30:29Z",
  "references": [
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      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-4720"
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      "type": "CVSS_V3"
    }
  ]
}



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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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