CVE-2025-39736

Medium

Description

In the Linux kernel, the following vulnerability has been resolved: mm/kmemleak: avoid deadlock by moving pr_warn() outside kmemleak_lock When netpoll is enabled, calling pr_warn_once() while holding kmemleak_lock in mem_pool_alloc() can cause a deadlock due to lock inversion with the netconsole subsystem. This occurs because pr_warn_once() may trigger netpoll, which eventually leads to __alloc_skb() and back into kmemleak code, attempting to reacquire kmemleak_lock. This is the path for the deadlock. mem_pool_alloc() -> raw_spin_lock_irqsave(&kmemleak_lock, flags); -> pr_warn_once() -> netconsole subsystem -> netpoll -> __alloc_skb -> __create_object -> raw_spin_lock_irqsave(&kmemleak_lock, flags); Fix this by setting a flag and issuing the pr_warn_once() after kmemleak_lock is released.

SeverityMedium
CVSS5.5
Exploit probability—
ProductLinux Kernel
PublishedSep 11, 2025
First seenSep 11, 2025
Weakness typeCWE-667CWE-667

How to fix

Affected products

ProductAffected versionsFixed in
linux linux_kernel5.4 ≤ v < 5.4.297, 5.5 ≤ v < 5.10.241, 5.11 ≤ v < 5.15.190, 5.16 ≤ v < 6.1.149, 6.2 ≤ v < 6.6.103, 6.7 ≤ v < 6.12.43, 6.13 ≤ v < 6.15.11, 6.16 ≤ v < 6.16.2, 6.175.4.297, 5.10.241, 5.15.190, 6.1.149, 6.6.103, 6.12.43, 6.15.11, 6.16.2
debian debian_linux11.0—

Check your version

Choose the product and enter the version you run to see whether it falls in the affected range.

In the Intelligence 360 plan

Attack Surface Management

See the assets tied to your domains, the technologies they run and known vulnerabilities in one list.