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CVE-2026-16361: Vulnerability in Mozilla Firefox

0
Critical
VulnerabilityCVE-2026-16361cvecve-2026-16361
Published: 07/21/2026 (07/21/2026, 12:38:27 UTC)
Source: CVE Database V5
Vendor/Project: Mozilla
Product: Firefox

Description

Memory safety bugs present in Firefox ESR 115.37 and Firefox ESR 140.12. 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 was fixed in Firefox ESR 115.38 and Firefox ESR 140.13.

CVSS v3.1

Score 9.8critical

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected software

GitHub Actionsmore threats →ai
mozilla/firefox
pkg:github/mozilla/firefox
Affected versions
>=115.37 <115.38>=140.12 <140.13

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AI-Powered Analysis

Machine-generated threat intelligence

AILast updated: 07/21/2026, 13:42:44 UTC

Technical Analysis

CVE-2026-16361 describes memory safety vulnerabilities in Mozilla Firefox ESR 115.37 and 140.12. These bugs involve memory corruption issues that could allow an attacker, with sufficient effort, to execute arbitrary code. Mozilla addressed these issues by releasing fixed versions Firefox ESR 115.38 and 140.13. The vulnerabilities were discovered and reported by the Mozilla Fuzzing Team. No active exploitation has been observed. The fixes are part of broader security updates addressing multiple high-impact vulnerabilities in Firefox ESR.

Potential Impact

The vulnerabilities could allow remote attackers to exploit memory corruption bugs to run arbitrary code within the context of the affected Firefox ESR versions. This could lead to compromise of the user's system or data if exploited. However, there are no known attacks in the wild at this time.

Mitigation Recommendations

Mozilla has released official fixes for these vulnerabilities in Firefox ESR versions 115.38 and 140.13. Users and administrators should update affected Firefox ESR installations to these or later versions to remediate the issue. Patch status is confirmed by the vendor advisories. No additional mitigation actions are indicated beyond applying the official updates.

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Technical Details

Data Version
5.2
Assigner Short Name
mozilla
Date Reserved
2026-07-20T21:56:10.203Z
Cvss Version
null
State
PUBLISHED
Remediation Level
null
Vendor Advisory Urls
[{"url":"https://www.mozilla.org/security/advisories/mfsa2026-69/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-70/","vendor":"Mozilla"}]

Threat ID: 6a5f6cbb2a4a8d5989262503

Added to database: 07/21/2026, 12:57:31 UTC

Last enriched: 07/21/2026, 13:42:44 UTC

Last updated: 07/21/2026, 22:51:54 UTC

Views: 5

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