CVEvulnerability
CVE-2026-99037
- Status
- Received
- Published
- 2026-10-23
- Last modified
- 2026-10-23
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Description
In the Linux kernel, the following vulnerability has been resolved:
dm-crypt: reject the lmk IV mode with AEAD ciphers
A "capi:" table line that pairs an AEAD cipher with the lmk IV mode,
for example "capi:gcm(aes)-lmk" with the integrity:28:aead option,
causes an oops when it is loaded. lmk sets tfms_count to 64, but
crypt_alloc_tfms_aead only allocates one transform, so crypt_setkey
reads past the end of the tfms_aead array and calls crypto_aead_setkey
on the values it finds there.
lmk exists for compatibility with Loop-AES, which uses CBC, so refuse
it with an AEAD cipher rather than allocate 64 AEAD transforms. The
check cannot go in crypt_iv_lmk_ctr with the other lmk checks, because
the IV constructor runs after crypt_set_key.
Note that this is not a security bug because the memory corruption can
only be triggered by root.
References
- https://git.kernel.org/stable/c/3195e0daf590683992edb4eed32269e569e04924 git.kernel.org
- https://git.kernel.org/stable/c/40ea7dfa8cd5f9aed72a55c9ca3008aee5880e6f git.kernel.org
- https://git.kernel.org/stable/c/962ce265fbf5d87afeb78cf19c12e083ab0ffeb8 git.kernel.org
- https://git.kernel.org/stable/c/9a0dab8a9d9975dec14a118b55cae2517aea5ca9 git.kernel.org
- https://git.kernel.org/stable/c/a1a875614dae43b43d311bb9e7a7a70eed78efe6 git.kernel.org