CVE-2026-53239

In the Linux kernel, the following vulnerability has been resolved: xfrm: policy: fix use-after-free on inexact bin in xfrm_policy_bysel_ctx() Fix the race by pruning the bin while still holding xfrm_policy_lock, before dropping it. Use __xfrm_policy_inexact_prune_bin() directly since the lock is already held. The wrapper xfrm_policy_inexact_prune_bin() becomes unused and is removed. Race: CPU0 (XFRM_MSG_DELPOLICY) CPU1 (XFRM_MSG_NEWSPDINFO) ========================== ========================== xfrm_policy_bysel_ctx(): spin_lock_bh(xfrm_policy_lock) bin = xfrm_policy_inexact_lookup() __xfrm_policy_unlink(pol) spin_unlock_bh(xfrm_policy_lock) xfrm_policy_kill(ret) // wide window, lock not held xfrm_hash_rebuild(): spin_lock_bh(xfrm_policy_lock) __xfrm_policy_inexact_flush(): kfree_rcu(bin) // bin freed spin_unlock_bh(xfrm_policy_lock) xfrm_policy_inexact_prune_bin(bin) // UAF: bin is freed

• linux linux kernel (>= 5.0 < 5.10.259) • linux linux kernel (>= 5.11 < 5.15.210) • linux linux kernel (>= 5.16 < 6.1.176) • linux linux kernel (>= 6.2 < 6.6.143) • linux linux kernel (>= 6.7 < 6.12.94) • linux linux kernel (>= 6.13 < 6.18.36) • linux linux kernel (>= 6.19 < 7.0.13) • linux linux kernel 7.1