Not yet scoredPublished Sep 4, 2026

CVE-2026-80843xfrm: fix xfrm_state_construct() auth-trunc leak

Updated under an hour ago (Oct 27, 2026, 6:00 AM ET)

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No exploitation reported and no EPSS estimate yet.

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Exploited in the last 30 days

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.

CVSS: Not yet scored
Weakness (CWE): Not given
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: Linux
NVD analysis: Received
Record last updated: Oct 19, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

Linux Linux linux:linux (from the name)	4447bb33f09444920a8f1d89e1540137429351b6 builds before 958ae9f261319e1cdc44879886bcda2263258cca; from 4447bb33f09444920a8f1d89e1540137429351b6 before fb7f3e74789a3c89647f4eb768f6dfaf4a751e72; from 4447bb33f09444920a8f1d89e1540137429351b6 before ba0c110c205855b3f1e3130d8c0fdb484d704c8c; from 4447bb33f09444920a8f1d89e1540137429351b6 before c8837bbe792257af547fd1c0252553ce13148795; 4447bb33f09444920a8f1d89e1540137429351b6 builds before 71d42da01740ec6557837bebec0bc48cfc3b4c39; from 4447bb33f09444920a8f1d89e1540137429351b6 before cf67361e78dca488d6e4df8396a53e6745a3a80e; from 4447bb33f09444920a8f1d89e1540137429351b6 before 37426395cb90ef217beec8407a14bd82153793d3; from 4447bb33f09444920a8f1d89e1540137429351b6 before be19d20e53a239572bb2a28efcc1cd2b069b1ef9; and 1 more ranges	CNA record

References

References

https://git.kernel.org/stable/c/958ae9f261319e1cdc44879886bcda2263258cca
https://git.kernel.org/stable/c/fb7f3e74789a3c89647f4eb768f6dfaf4a751e72
https://git.kernel.org/stable/c/ba0c110c205855b3f1e3130d8c0fdb484d704c8c
https://git.kernel.org/stable/c/c8837bbe792257af547fd1c0252553ce13148795
https://git.kernel.org/stable/c/71d42da01740ec6557837bebec0bc48cfc3b4c39
https://git.kernel.org/stable/c/cf67361e78dca488d6e4df8396a53e6745a3a80e
https://git.kernel.org/stable/c/37426395cb90ef217beec8407a14bd82153793d3
https://git.kernel.org/stable/c/be19d20e53a239572bb2a28efcc1cd2b069b1ef9
https://git.kernel.org/stable/c/c12cbf56320fb633484ee0ca1fb7d68d6b64b213

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.