Improper locking in Linux kernel - CVE-2025-39932

 

Improper locking in Linux kernel - CVE-2025-39932

Published: October 4, 2025


Vulnerability identifier: #VU116468
CSH Severity: Low
CVSS v4: 6.8 [CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2025-39932
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 smbd_destroy() function in fs/smb/client/smbdirect.c. A local user can perform a denial of service (DoS) attack.


Affected software

Linux kernel
Ubuntu
openEuler
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
kernel-extra-modules
linux (Ubuntu package)
linux-aws-fips (Ubuntu package)
linux-xilinx (Ubuntu package)
linux-nvidia (Ubuntu package)
linux-aws-6.8 (Ubuntu package)
linux-raspi (Ubuntu package)
linux-azure (Ubuntu package)
linux-azure-6.8 (Ubuntu package)
linux-azure-fips (Ubuntu package)
linux-realtime (Ubuntu package)

How to mitigate CVE-2025-39932

Install update from vendor's repository.

python3-perf-debuginfo - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.17.150
kernel - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.17.150
bpftool - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.17.150
bpftool-debuginfo - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.17.150
kernel-debuginfo - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.17.150
kernel-debugsource - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.17.150
kernel-devel - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.17.150
kernel-headers - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.17.150
kernel-tools - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.17.150
kernel-tools-debuginfo - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.17.150
kernel-tools-devel - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.17.150
perf - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.17.150
perf-debuginfo - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.17.150
python3-perf - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.17.150
kernel-source - addressed in versions 6.6.0-145.1.19.156, 6.6.0-145.3.17.150
kernel-extra-modules - update to 6.6.0-145.3.17.150
linux (Ubuntu package) - addressed in versions 6.8.0-106.106, 6.8.0-106.106.1, 6.8.0-106.106.1~22.04.1, 6.8.0-106.106~22.04.1, 6.8.0-1035.38, 6.8.0-1047.48, 6.8.0-1047.48~22.04.1, 6.8.0-1048.53, 6.8.0-1049.49, 6.8.0-1049.49~22.04.1, 6.8.0-1050.53, 6.8.0-1052.55, 6.8.0-1052.55~22.04.1
linux-aws-fips (Ubuntu package) - addressed in versions 6.8.0-106.106+fips1, 6.8.0-1050.53+fips1, 6.8.0-1052.55+fips1
linux-xilinx (Ubuntu package) - update to 6.8.0-1029.30
linux-nvidia (Ubuntu package) - addressed in versions 6.8.0-1049.52, 6.8.0-1049.52.1, 6.8.0-1049.52~22.04.1
linux-aws-6.8 (Ubuntu package) - update to 6.8.0-1050.53~22.04.1
linux-raspi (Ubuntu package) - addressed in versions 6.8.0-1050.54, 6.8.0-2040.41
linux-azure (Ubuntu package) - update to 6.8.0-1051.57
linux-azure-6.8 (Ubuntu package) - update to 6.8.0-1051.57~22.04.1
linux-azure-fips (Ubuntu package) - update to 6.8.0-1052.58+fips1
linux-realtime (Ubuntu package) - addressed in versions 6.8.1-1045.46, 6.8.1-1045.46~22.04.1

External References

Related Security Bulletins