CVE-2023-4207

high

Published 2023-11-07 · Modified 2023-11-14

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CVSS v3

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CVSS v4 NEW

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not yet in upstream

VIR risk

8.0

Description

A use-after-free vulnerability in the Linux kernel's net/sched: cls_fw component can be exploited to achieve local privilege escalation. When fw_change() is called on an existing filter, the whole tcf_result struct is always copied into the new instance of the filter. This causes a problem when updating a filter bound to a class, as tcf_unbind_filter() is always called on the old instance in the success path, decreasing filter_cnt of the still referenced class and allowing it to be deleted, leading to a use-after-free. We recommend upgrading past commit 76e42ae831991c828cffa8c37736ebfb831ad5ec.

Predictions

Exploit likelihood

20%

Patch ETA

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Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

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OS impact

AlmaLinux Fixed 1 release

Version	Status	Fixed in
8	Fixed	`kernel-doc-4.18.0-513.5.1.el8_9.noarch.rpm`

Debian Fixed 5 releases

Version	Status	Fixed in
trixie	Fixed	`6.4.11-1`
sid	Fixed	`6.4.11-1`
forky	Fixed	`6.4.11-1`
bullseye	Fixed	`5.10.191-1`
bookworm	Fixed	`6.1.52-1`

Red Hat Fixed 2 releases

Version	Status	Fixed in
9	Fixed	—
8	Fixed	—

References

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.