CVE-2025-26695: thunderbird — Fix

Description

When requesting an OpenPGP key from a WKD server, an incorrect padding size was used and a network observer could have learned the length of the requested email address. This vulnerability was fixed in Thunderbird 136 and Thunderbird 128.8.

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CVSS v3.1 Score

5.3

MEDIUM

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

Affected Products

Vendor	Product	Versions
mozilla	thunderbird	< 128.8.0
mozilla	thunderbird	129.0 — 136.0

References

Advisories & Patches

https://www.mozilla.org/security/advisories/mfsa2025-17/ https://www.mozilla.org/security/advisories/mfsa2025-18/

Other References

https://bugzilla.mozilla.org/show_bug.cgi?id=1883039

Frequently Asked Questions

What is CVE-2025-26695? +

When requesting an OpenPGP key from a WKD server, an incorrect padding size was used and a network observer could have learned the length of the requested email address. This vulnerability was fixed in Thunderbird 136 and Thunderbird 128.8. It has a CVSS v3.1 base score of 5.3 (MEDIUM).

How severe is CVE-2025-26695? +

CVE-2025-26695 has a CVSS v3.1 score of 5.3 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2025-26695? +

CVE-2025-26695 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-2025-26695? +

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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CVE-2025-26695