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vulnerability

Red Hat: CVE-2021-47232: kernel: can: j1939: fix Use-after-Free, hold skb ref while in use

Severity
5
CVSS
(AV:L/AC:L/Au:S/C:N/I:N/A:C)
Published
May 21, 2024
Added
Jul 9, 2025
Modified
Jul 10, 2025

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.

Solution

no-fix-redhat-rpm-package
Title
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