CVE-2026-72451

Summary

In the Linux kernel, the following vulnerability has been resolved:

xfrm: Fix xfrm state cache insertion race

The xfrm input state cache insertion code checks the validity of the state before acquiring the global xfrm_state_lock. Thus it's possible for someone else to kill the state after it passed the validity check, and then the insertion will add the dead state to the cache.

Fix this by moving the validity check inside the lock.

This entire function is called on the input path, where BH must be off (e.g., the caller of this function xfrm_input acquires its spinlocks without disabling BH).

So there is no need to disable BH here or take the RCU read lock. Remove both and replace them with an assertion that trips if BH is accidentally enabled on some future calling path.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux5e4334dc39443645415450163ff5ff1ee7e79784 < 6dab4dec9a49121d079981ac913569f232c06b06affected
LinuxLinux81a331a0e72ddc2f75092603d9577bd1a0ca23ad < a1a3360a0c44b8b5c134db2a9d0667b61c9cf523affected
LinuxLinux81a331a0e72ddc2f75092603d9577bd1a0ca23ad < 041859fd55c81ea55e76d051e39b7b79975b8c7daffected
LinuxLinux81a331a0e72ddc2f75092603d9577bd1a0ca23ad < ddd3d0132920319ac426e12456013eadbae67e15affected
LinuxLinux6.12.13 < 6.12.97affected
LinuxLinux6.13affected
LinuxLinux0 < 6.13unaffected
LinuxLinux6.12.97 <= 6.12.*unaffected
LinuxLinux6.18.40 <= 6.18.*unaffected
LinuxLinux7.1.5 <= 7.1.*unaffected
LinuxLinux7.2 <= *unaffected

Weaknesses

References