CVE-2026-53389
In the Linux kernel, the following vulnerability has been resolved: net/tcp-ao: fix use-after-free of key in del_async path In tcp_ao_delete_key(), the del_async path skips the current_key and rnext_key validity checks present in the synchronous path, assuming these pointers are always NULL on LISTEN sockets. However, if a key was added with set_current=1/set_rnext=1 while the socket was in CLOSE state, current_key and rnext_key will be non-NULL after listen() transitions the socket to LISTEN. When such a key is deleted with del_async=1, hlist_del_rcu() and call_rcu() free the key without clearing the dangling pointers. After the RCU grace period, getsockopt(TCP_AO_INFO) dereferences current_key->sndid and rnext_key->rcvid from freed slab memory. Clear current_key and rnext_key in the del_async path when they reference the key being deleted.
Affected versions
Linux kernel versions
6.7
and later are affected. Fixed in
6.12.95,
6.18.38,
7.1.3,
7.2-rc1
and their respective stable series.
References
4 totalFrequently asked questions
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What is CVE-2026-53389?
CVE-2026-53389 is a unscored severity Linux kernel vulnerability . It affects Linux kernel versions from 6.7 onward and has been patched in 6.12.95, 6.18.38, 7.1.3 and others. CVE-2026-53389 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
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Is there a patch available for CVE-2026-53389?
Yes — CVE-2026-53389 has been patched. Fixed versions include 6.12.95, 6.18.38, 7.1.3 and others. If you are running Linux kernel 6.7 or later up to the fix versions, apply the relevant patch for your kernel branch.
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Is CVE-2026-53389 actively exploited?
No — CVE-2026-53389 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.