CVE-2021-47232

can: j1939: fix Use-after-Free, hold skb ref while in use

State: Published
Severity: 9.8 Critical
Published: May 21, 2024
Updated: Aug 5, 2026
Reserved: Apr 10, 2024

Description

In the Linux kernel, the following vulnerability has been resolved:

can: j1939: fix Use-after-Free, hold skb ref while in use

This patch fixes a Use-after-Free found by the syzbot.

The problem is that a skb is taken from the per-session skb queue, without incrementing the ref count. This leads to a Use-after-Free if the skb is taken concurrently from the session queue due to a CTS.

Scores

CVSS	Score	Vector	Source
3.1	9.8 Critical	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H	Linux
3.1	8.4 High	CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H	CISA-ADP

Weaknesses

CWE-416 Use After Free

Affected Products

Product	Versions
LinuxLinux	9d71dd0c70099914fcd063135da3c580865e924c to before 22cba878abf646cd3a02ee7c8c2cef7afe66a256Affected 9d71dd0c70099914fcd063135da3c580865e924c to before 509ab6bfdd0c76daebbad0f0af07da712116de22Affected 9d71dd0c70099914fcd063135da3c580865e924c to before 1071065eeb33d32b7d98c2ce7591881ae7381705Affected 9d71dd0c70099914fcd063135da3c580865e924c to before 2030043e616cab40f510299f09b636285e0a3678Affected
LinuxLinux	5.4Affected before 5.4Not affected 5.4.128 through 5.4.Not affected 5.10.46 through 5.10.Not affected 5.12.13 through 5.12.*Not affected 5.13 and laterNot affected

References

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