Description
In GnuPG before 2.4.9, armor_filter in g10/armor.c has two increments of an index variable where one is intended, leading to an out-of-bounds write for crafted input. (For ExtendedLTS, 2.2.51 and later are fixed versions.)
Affected products
gnupg: gnupg
References10
- github.com/gpg/gnupg/commit/115d138ba599328005c5321c0ef9f003558… Patch
- github.com/gpg/gnupg/compare/gnupg-2.2.50...gnupg-2.2.51 Patch
- www.openwall.com/lists/oss-security/2025/12/29/11 Mailing ListPatch
- github.com/gpg/gnupg/blob/ff30683418695f5d2cc9e6cf8c9418e09378e… Product
- gpg.fail/memcpy Broken Link
- media.ccc.de/v/39c3-to-sign-or-not-to-sign-practical-vulnerabil… Issue Tracking
- news.ycombinator.com/item?id=46403200 Issue Tracking
- www.openwall.com/lists/oss-security/2025/12/28/5 Mailing List
- lists.debian.org/debian-lts-announce/2026/01/msg00008.html
- gpg.fail/memcpy Broken Link
Metrics
- CVSS 3.1
-
7.0
HIGH
Score source: NVD
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 4 · as of 11 November 2026
- CWE
- CWE-675CWE-787
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