CVE-2023-4622 Use-after-free in Linux kernel's af_unix component

High 7.8 Published 6 Sep 2023 Updated 17 Sep 2026

A use-after-free in the Linux kernel's af_unix component allows local attackers to escalate privileges due to a race condition.

Exploited in the wild: Not known
Login needed: Any signed-in user
Attackable: Local or same network only
Victim action needed: Not needed
Fix: Available

What is CVE-2023-4622?

CVE-2023-4622 is a high-severity use after free vulnerability in Debian Debian Linux, published on 6 Sep 2023. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

A use-after-free vulnerability in the Linux kernel's af_unix component can be exploited to achieve local privilege escalation.

The unix_stream_sendpage() function tries to add data to the last skb in the peer's recv queue without locking the queue. Thus there is a race where unix_stream_sendpage() could access an skb locklessly that is being released by garbage collection, resulting in use-after-free.

We recommend upgrading past commit 790c2f9d15b594350ae9bca7b236f2b1859de02c (or backported equivalents).

Weakness: CWE-416

Which versions are affected by CVE-2023-4622?

It affects 2 products.

Linux distribution packages (5)

`kgraft-patch-SLE12-SP5_Update_39` SUSE:Linux Enterprise Live Patching 12 SP5	All versions	`10-2.2`
`kgraft-patch-SLE12-SP5_Update_42` SUSE:Linux Enterprise Live Patching 12 SP5	All versions	`8-2.1`
`kgraft-patch-SLE12-SP5_Update_47` SUSE:Linux Enterprise Live Patching 12 SP5	All versions	`4-2.1`
`kernel-livepatch-SLE15-SP1_Update_36` SUSE:Linux Enterprise Live Patching 15 SP1	All versions	`11-150100.2.2`
`kernel-livepatch-SLE15-SP1_Update_38` SUSE:Linux Enterprise Live Patching 15 SP1	All versions	`8-150100.2.1`

Products include Debian Debian Linux, Linux kernel.

How do I fix CVE-2023-4622?

Apply the vendor's patch.

Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.

Is CVE-2023-4622 being exploited?

There is no known exploitation of CVE-2023-4622 in the wild and no public exploit code.

Public exploit code: 1 proofs of concept on GitHub.

All Debian Debian Linux vulnerabilities

Sources

Also known as A-299123598, ASB-A-299123598, AZL-28679, AZL-31642, DEBIAN-CVE-2023-4622, GHSA-hxpr-87wq-jwf8 and 5 more.