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 affects Thunderbird < 136 and Thunderbird < 128.8.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTNIST
5.3 MEDIUM
LOCAL
LOW
LOW
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L
mozillaCNA
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CISA-ADPADP
5.3 MEDIUM
LOCAL
LOW
LOW
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L
Base Score
CVSS 3.x
EPSS Score
Percentile: 3%
VendorProductVersion
mozillathunderbird
𝑥
< 128.8.0
mozillathunderbird
129.0 ≤
𝑥
< 136.0
𝑥
= Vulnerable software versions
Debian logo
Debian Releases
Debian Product
Codename
thunderbird
bullseye
vulnerable
bullseye (security)
1:128.11.0esr-1~deb11u1
fixed
bookworm
1:128.10.0esr-1~deb12u1
fixed
bookworm (security)
1:128.11.0esr-1~deb12u1
fixed
trixie
1:128.10.0esr-1
fixed
sid
1:128.11.0esr-1
fixed
References
https://bugzilla.mozilla.org/show_bug.cgi?id=1883039
https://www.mozilla.org/security/advisories/mfsa2025-17/
https://www.mozilla.org/security/advisories/mfsa2025-18/