CVE-2025-5262: thunderbird Double Free — Fix

Description

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.

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CVSS v3.1 Score

7.5

HIGH

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

Weakness Type (CWE)

CWE-415 CWE-415

Affected Products

Vendor	Product	Versions
mozilla	thunderbird	< 128.11.0
mozilla	thunderbird	< 139.0

References

Advisories & Patches

https://www.mozilla.org/security/advisories/mfsa2025-45/ https://www.mozilla.org/security/advisories/mfsa2025-46/

Other References

https://bugzilla.mozilla.org/show_bug.cgi?id=1962421

Frequently Asked Questions

What is CVE-2025-5262? +

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. It has a CVSS v3.1 base score of 7.5 (HIGH).

How severe is CVE-2025-5262? +

CVE-2025-5262 has a CVSS v3.1 score of 7.5 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.

What products are affected by CVE-2025-5262? +

CVE-2025-5262 affects products from mozilla, specifically: thunderbird. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-5262? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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