CVE-2026-80843

Summary

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.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux4447bb33f09444920a8f1d89e1540137429351b6 < 958ae9f261319e1cdc44879886bcda2263258ccaaffected
LinuxLinux4447bb33f09444920a8f1d89e1540137429351b6 < fb7f3e74789a3c89647f4eb768f6dfaf4a751e72affected
LinuxLinux4447bb33f09444920a8f1d89e1540137429351b6 < ba0c110c205855b3f1e3130d8c0fdb484d704c8caffected
LinuxLinux4447bb33f09444920a8f1d89e1540137429351b6 < c8837bbe792257af547fd1c0252553ce13148795affected
LinuxLinux4447bb33f09444920a8f1d89e1540137429351b6 < 71d42da01740ec6557837bebec0bc48cfc3b4c39affected
LinuxLinux4447bb33f09444920a8f1d89e1540137429351b6 < cf67361e78dca488d6e4df8396a53e6745a3a80eaffected
LinuxLinux4447bb33f09444920a8f1d89e1540137429351b6 < 37426395cb90ef217beec8407a14bd82153793d3affected
LinuxLinux4447bb33f09444920a8f1d89e1540137429351b6 < be19d20e53a239572bb2a28efcc1cd2b069b1ef9affected
LinuxLinux4447bb33f09444920a8f1d89e1540137429351b6 < c12cbf56320fb633484ee0ca1fb7d68d6b64b213affected
LinuxLinux2.6.33affected
LinuxLinux0 < 2.6.33unaffected
LinuxLinux5.10.269 <= 5.10.*unaffected
LinuxLinux5.15.220 <= 5.15.*unaffected
LinuxLinux6.1.187 <= 6.1.*unaffected
LinuxLinux6.6.156 <= 6.6.*unaffected
LinuxLinux6.12.108 <= 6.12.*unaffected
LinuxLinux6.18.49 <= 6.18.*unaffected
LinuxLinux7.1.13 <= 7.1.*unaffected
LinuxLinux7.2.3 <= 7.2.*unaffected
LinuxLinux7.3-rc1 <= *unaffected

Weaknesses

References