Improper locking in Linux kernel - CVE-2025-21986

 

Improper locking in Linux kernel - CVE-2025-21986

Published: April 2, 2025 / Updated: May 11, 2025


Vulnerability identifier: #VU106741
CSH Severity: Low
CVSS v4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2025-21986
CWE-ID: CWE-667
Exploitation vector: Local access
Exploit availability: No public exploit available

Vulnerability details

The vulnerability allows a local user to perform a denial of service (DoS) attack.

The vulnerability exists due to improper locking within the switchdev_port_obj_act_is_deferred(), EXPORT_SYMBOL_GPL() and call_switchdev_blocking_notifiers() functions in net/switchdev/switchdev.c. A local user can perform a denial of service (DoS) attack.


Affected software

Linux kernel
Debian Linux
Ubuntu
openEuler
linux (Debian package)
python3-perf-debuginfo
kernel
bpftool
bpftool-debuginfo
kernel-debuginfo
kernel-debugsource
kernel-devel
kernel-headers
kernel-tools
kernel-tools-debuginfo
kernel-tools-devel
perf
perf-debuginfo
python3-perf
kernel-source
linux (Ubuntu package)
linux-hwe-6.8 (Ubuntu package)
linux-azure-nvidia (Ubuntu package)
linux-azure (Ubuntu package)
linux-ibm (Ubuntu package)
linux-oracle (Ubuntu package)
linux-oracle-6.8 (Ubuntu package)
linux-aws-6.8 (Ubuntu package)
linux-nvidia (Ubuntu package)
linux-raspi (Ubuntu package)
linux-raspi-realtime (Ubuntu package)
linux-realtime (Ubuntu package)
linux-realtime-6.8 (Ubuntu package)
linux-lowlatency (Ubuntu package)
linux-oem-6.11 (Ubuntu package)

How to mitigate CVE-2025-21986

Install update from vendor's website.

Linux kernel - update to 6.13.8
linux (Debian package) - update to 6.1.133-1
python3-perf-debuginfo - addressed in versions 6.6.0-145.0.12.138, 6.6.0-145.1.12.150
kernel - addressed in versions 6.6.0-145.0.12.138, 6.6.0-145.1.12.150
bpftool - addressed in versions 6.6.0-145.0.12.138, 6.6.0-145.1.12.150
bpftool-debuginfo - addressed in versions 6.6.0-145.0.12.138, 6.6.0-145.1.12.150
kernel-debuginfo - addressed in versions 6.6.0-145.0.12.138, 6.6.0-145.1.12.150
kernel-debugsource - addressed in versions 6.6.0-145.0.12.138, 6.6.0-145.1.12.150
kernel-devel - addressed in versions 6.6.0-145.0.12.138, 6.6.0-145.1.12.150
kernel-headers - addressed in versions 6.6.0-145.0.12.138, 6.6.0-145.1.12.150
kernel-tools - addressed in versions 6.6.0-145.0.12.138, 6.6.0-145.1.12.150
kernel-tools-debuginfo - addressed in versions 6.6.0-145.0.12.138, 6.6.0-145.1.12.150
kernel-tools-devel - addressed in versions 6.6.0-145.0.12.138, 6.6.0-145.1.12.150
perf - addressed in versions 6.6.0-145.0.12.138, 6.6.0-145.1.12.150
perf-debuginfo - addressed in versions 6.6.0-145.0.12.138, 6.6.0-145.1.12.150
python3-perf - addressed in versions 6.6.0-145.0.12.138, 6.6.0-145.1.12.150
kernel-source - addressed in versions 6.6.0-145.0.12.138, 6.6.0-145.1.12.150
linux (Ubuntu package) - addressed in versions 6.8.0-84.84, 6.8.0-84.84.1, 6.8.0-84.84.1~22.04.1, 6.8.0-1023.25, 6.8.0-1036.40, 6.8.0-1039.41, 6.8.0-1040.42, 6.11.0-28.28, 6.11.0-28.28~24.04.1, 6.11.0-1011.11, 6.11.0-1014.14, 6.11.0-1015.16, 6.11.0-1016.16, 6.11.0-1016.16~24.04.1, 6.11.0-1017.18
linux-hwe-6.8 (Ubuntu package) - addressed in versions 6.8.0-84.84~22.04.1, 6.8.0-85.85~22.04.1
linux-azure-nvidia (Ubuntu package) - update to 6.8.0-1025.27
linux-azure (Ubuntu package) - addressed in versions 6.8.0-1036.42~22.04.1, 6.8.0-1038.44, 6.11.0-1018.18, 6.11.0-1018.18~24.04.1
linux-ibm (Ubuntu package) - addressed in versions 6.8.0-1037.37, 6.8.0-1037.37~22.04.1
linux-oracle (Ubuntu package) - update to 6.8.0-1037.38
linux-oracle-6.8 (Ubuntu package) - update to 6.8.0-1037.38~22.04.1
linux-aws-6.8 (Ubuntu package) - addressed in versions 6.8.0-1039.41~22.04.1, 6.8.0-1040.42~22.04.1
linux-nvidia (Ubuntu package) - addressed in versions 6.8.0-1039.42, 6.8.0-1039.42.1, 6.8.0-1039.42~22.04.1
linux-raspi (Ubuntu package) - update to 6.8.0-1039.43
linux-raspi-realtime (Ubuntu package) - update to 6.8.0-2031.32
linux-realtime (Ubuntu package) - update to 6.8.1-1034.35
linux-realtime-6.8 (Ubuntu package) - update to 6.8.1-1034.35~22.04.1
linux-lowlatency (Ubuntu package) - addressed in versions 6.11.0-1015.16, 6.11.0-1015.16~24.04.2
linux-oem-6.11 (Ubuntu package) - update to 6.11.0-1024.24

External References

Related Security Bulletins