Use After Free Affecting linux-6.1 package, versions <6.1.153-1~deb11u1


Severity

Recommended
0.0
high
0
10

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Threat Intelligence

EPSS
0.16% (5th percentile)

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  • Snyk IDSNYK-DEBIAN11-LINUX61-13542175
  • published14 Oct 2025
  • disclosed23 Sept 2025

Introduced: 23 Sep 2025

CVE-2025-39873  (opens in a new tab)
CWE-416  (opens in a new tab)

How to fix?

Upgrade Debian:11 linux-6.1 to version 6.1.153-1~deb11u1 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream linux-6.1 package and not the linux-6.1 package as distributed by Debian. See How to fix? for Debian:11 relevant fixed versions and status.

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

can: xilinx_can: xcan_write_frame(): fix use-after-free of transmitted SKB

can_put_echo_skb() takes ownership of the SKB and it may be freed during or after the call.

However, xilinx_can xcan_write_frame() keeps using SKB after the call.

Fix that by only calling can_put_echo_skb() after the code is done touching the SKB.

The tx_lock is held for the entire xcan_write_frame() execution and also on the can_get_echo_skb() side so the order of operations does not matter.

An earlier fix commit 3d3c817c3a40 ("can: xilinx_can: Fix usage of skb memory") did not move the can_put_echo_skb() call far enough.

[mkl: add "commit" in front of sha1 in patch description] [mkl: fix indention]

CVSS Base Scores

version 3.1