VYPR
← All advisories
High severity7.8NVD Advisory· Published Jun 25, 2026· Updated Sep 8, 2026

CVE-2026-53239

CVE-2026-53239

Description

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

AI Insight

LLM-synthesized narrative grounded in this CVE's description and references.

Affected products

105

Patches

Vulnerability mechanics

References

9

News mentions

1