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CVE-2023-4622

Status: ModifiedHigh (7)—💥 PoC

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).

CVSS

Exploitation probability (EPSS)

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

💥 Public exploits

Exploit code or detection templates are publicly available. This is not the same as confirmed active exploitation (KEV), but it raises the risk: patch with priority.

⚠️ GitHub proofs of concept are not verified: some are fake or contain malware. Never run them outside an isolated lab.

Affected technologies (2)

Debian — Debian LinuxLinux — Linux Kernel

CWEs

References

Raw JSON (NVD)

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      "value": "A use-after-free vulnerability in the Linux kernel's af_unix component can be exploited to achieve local privilege escalation.\n\n\n\nThe 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.\n\n\n\nWe recommend upgrading past commit 790c2f9d15b594350ae9bca7b236f2b1859de02c (or backported equivalents)."
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