Memory Safety Vulnerability in Mozilla Firefox and Thunderbird
CVE-2025-4091

6.5MEDIUM

Key Information:

Vendor

Mozilla

Vendor
CVE Published:
29 April 2025

What is CVE-2025-4091?

This vulnerability manifests as memory safety bugs in Mozilla Firefox and Thunderbird, allowing potential memory corruption. Specific versions of Firefox and Thunderbird are affected, and although evidence suggests the likelihood of exploitability for arbitrary code execution exists, detailed exploitation has not been demonstrated. Users of versions prior to Firefox 138 and Thunderbird 138 should upgrade to the latest versions to protect against potential threats. Regular updates and security measures are essential for maintaining system integrity.

Affected Version(s)

Firefox < 138

Firefox ESR < 128.10

Thunderbird < 138

References

CVSS V3.1

Score:
6.5
Severity:
MEDIUM
Confidentiality:
Low
Integrity:
Low
Availability:
Low
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Maurice Dauer and the Mozilla Fuzzing Team
.
CVE-2025-4091 : Memory Safety Vulnerability in Mozilla Firefox and Thunderbird