CVE-2026-80843

medium

Description

In the Linux kernel, the following vulnerability has been resolved: xfrm: fix xfrm_state_construct() auth-trunc leak attach_auth_trunc() can allocate x->aalg while leaving x->props.aalgo at zero when the selected auth algorithm has no sadb_alg_id. One real case is cmac(aes). xfrm_state_construct() then treats !x->props.aalgo as "no auth algorithm attached yet" and calls attach_auth(). That overwrites x->aalg and loses the first allocation. Any later failure or teardown only frees the replacement pointer. Check whether x->aalg is already attached instead of inferring that state from x->props.aalgo.

References

https://git.kernel.org/stable/c/fb7f3e74789a3c89647f4eb768f6dfaf4a751e72

https://git.kernel.org/stable/c/cf67361e78dca488d6e4df8396a53e6745a3a80e

https://git.kernel.org/stable/c/c8837bbe792257af547fd1c0252553ce13148795

https://git.kernel.org/stable/c/c12cbf56320fb633484ee0ca1fb7d68d6b64b213

https://git.kernel.org/stable/c/be19d20e53a239572bb2a28efcc1cd2b069b1ef9

https://git.kernel.org/stable/c/ba0c110c205855b3f1e3130d8c0fdb484d704c8c

https://git.kernel.org/stable/c/958ae9f261319e1cdc44879886bcda2263258cca

https://git.kernel.org/stable/c/71d42da01740ec6557837bebec0bc48cfc3b4c39

https://git.kernel.org/stable/c/37426395cb90ef217beec8407a14bd82153793d3

Details

Source: Mitre, NVD

Published: 2026-09-04

Updated: 2026-09-04

Risk Information

CVSS v2

Base Score: 5

Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:N/A:N

Severity: Medium

CVSS v3

Base Score: 5.5

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

Severity: Medium

EPSS

EPSS: 0.00195