Out-of-bounds read in Linux kernel - CVE-2025-40008

 

Out-of-bounds read in Linux kernel - CVE-2025-40008

Published: October 21, 2025


Vulnerability identifier: #VU117401
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-2025-40008
CWE-ID: CWE-125
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 an out-of-bounds read error within the DEFINE_TEST_MEMSETXX() function in mm/kmsan/kmsan_test.c. A local user can perform a denial of service (DoS) attack.


Affected software

Linux kernel
Debian Linux
Ubuntu
linux (Debian package)
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-2025-40008

Install update from vendor's repository.

linux (Debian package) - update to 6.1.158-1
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