What is the CVSS score of CVE-2025-5262?

CVE-2025-5262 has a CVSS 3.1 base score of 7.5 (High). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. EPSS exploitation probability: 0.4%.

Which versions of Thunderbird are affected by CVE-2025-5262?

CVE-2025-5262 presents notable security risk rated CVSS 7.5. Exploitation could compromise the security of affected deployments.. A patch is available.

How to fix or mitigate CVE-2025-5262?

Within 30 days: Identify all affected systems and apply vendor patches as part of regular patch cycle. Monitor vendor channels for patch availability.

Thunderbird CVE-2025-5262

HIGH

Double Free (CWE-415)

2025-05-27 security@mozilla.org

Buffer Overflow Red Hat Mozilla Thunderbird Suse

7.5

CVSS 3.1

CVSS VectorNVD

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Lifecycle Timeline

Patch released

Apr 06, 2026 - 14:30 nvd

Patch available

Analysis Generated

Mar 28, 2026 - 18:44 vuln.today

CVE Published

May 27, 2025 - 13:15 nvd

HIGH 7.5

DescriptionNVD

A double-free could have occurred in vpx_codec_enc_init_multi after a failed allocation when initializing the encoder for WebRTC. This could have caused memory corruption and a potentially exploitable crash. This vulnerability affects Thunderbird < 139 and Thunderbird < 128.11.

AnalysisAI

A double-free could have occurred in vpx_codec_enc_init_multi after a failed allocation when initializing the encoder for WebRTC. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.

Technical ContextAI

This vulnerability is classified under CWE-415. A double-free could have occurred in vpx_codec_enc_init_multi after a failed allocation when initializing the encoder for WebRTC. This could have caused memory corruption and a potentially exploitable crash. This vulnerability affects Thunderbird < 139 and Thunderbird < 128.11. Affected products include: Mozilla Thunderbird.

RemediationAI

No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.