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EPSS 0.2%top 94%

CVE-2026-12330: Vulnerability in Mozilla Firefox

0
Medium
VulnerabilityCVE-2026-12330cvecve-2026-12330
Published: 06/16/2026 (06/16/2026, 11:53:03 UTC)
Source: CVE Database V5
Vendor/Project: Mozilla
Product: Firefox

Description

Incorrect boundary conditions in the Internationalization component. This vulnerability was fixed in Firefox ESR 140.12, Firefox ESR 115.37, and Thunderbird 140.12.

CVSS v3.1

Score 5.4medium

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

Affected software

Affected versions
>=115.0 <115.37>=140.0 <140.12

AI-Powered Analysis

Machine-generated threat intelligence

AILast updated: 06/17/2026, 08:16:53 UTC

Technical Analysis

This vulnerability involves incorrect boundary conditions in the Internationalization component of Mozilla Firefox, which could potentially lead to memory safety issues. It is classified under CWE-119, indicating a buffer boundary error. The issue was addressed and fixed in Firefox ESR 140.12 and Firefox ESR 115.37, as well as Thunderbird 140.12. The CVSS 3.1 vector indicates the vulnerability is remotely exploitable without privileges, requires user interaction, and impacts confidentiality and integrity with no impact on availability.

Potential Impact

The vulnerability could allow an attacker to cause limited confidentiality and integrity impacts due to incorrect boundary checks in the Internationalization component. The CVSS score of 5.4 reflects a medium severity risk. There are no reports of active exploitation in the wild. The flaw could potentially be leveraged to read or alter data improperly within the affected component.

Mitigation Recommendations

Mozilla has released official fixes for this vulnerability in Firefox ESR 140.12, Firefox ESR 115.37, and Thunderbird 140.12. Users and administrators should upgrade to these versions or later to remediate the issue. Since the vulnerability is fixed in these ESR releases, no additional mitigation steps are required beyond applying the official updates.

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Technical Details

Data Version
5.2
Assigner Short Name
mozilla
Date Reserved
2026-06-15T15:08:22.804Z
Cvss Version
null
State
PUBLISHED
Remediation Level
null
Vendor Advisory Urls
[{"url":"https://www.mozilla.org/security/advisories/mfsa2026-58/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-59/","vendor":"Mozilla"}]

Threat ID: 6a314c870b89be6888b4cf50

Added to database: 06/16/2026, 13:15:51 UTC

Last enriched: 06/17/2026, 08:16:53 UTC

Last updated: 07/31/2026, 19:22:57 UTC

Views: 70

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