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CVE-2025-49709: Vulnerability in Mozilla Firefox

0
Critical
VulnerabilityCVE-2025-49709cvecve-2025-49709
Published: 06/11/2025 (06/11/2025, 12:07:49 UTC)
Source: CVE Database V5
Vendor/Project: Mozilla
Product: Firefox

Description

Certain canvas operations could have lead to memory corruption. This vulnerability was fixed in Firefox 139.0.4.

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

Affected versions
<139.0.4

AI-Powered Analysis

Machine-generated threat intelligence

AILast updated: 07/30/2026, 01:01:09 UTC

Technical Analysis

CVE-2025-49709 is a vulnerability in Mozilla Firefox where certain canvas operations could cause memory corruption. This vulnerability is classified under CWE-787 (Out-of-bounds Write). It was addressed and fixed in Firefox version 139.0.4. The CVSS v3.1 base score is 9.8, indicating a critical severity with network attack vector, low attack complexity, no privileges required, no user interaction, and high impact on confidentiality, integrity, and availability. The vendor advisory confirms the fix and provides additional context on the issue.

Potential Impact

Successful exploitation of this vulnerability could allow an attacker to execute arbitrary code or cause a denial of service due to memory corruption. The high CVSS score reflects the potential for complete system compromise without requiring user interaction or privileges.

Mitigation Recommendations

Users and administrators should update Mozilla Firefox to version 139.0.4 or later to remediate this vulnerability. The vendor advisory confirms that the issue is fixed in this version. No additional mitigation steps are required beyond applying the official update.

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Technical Details

Data Version
5.1
Assigner Short Name
mozilla
Date Reserved
2025-06-09T20:17:23.292Z
State
PUBLISHED
Vendor Advisory Urls
[{"url":"https://www.mozilla.org/security/advisories/mfsa2025-47/","vendor":"Mozilla"}]

Threat ID: 6849756223110031d40fa8c2

Added to database: 06/11/2025, 12:24:02 UTC

Last enriched: 07/30/2026, 01:01:09 UTC

Last updated: 09/10/2026, 19:36:50 UTC

Views: 159

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