Buffer overflow in Linux kernel - CVE-2025-39727
Published: September 8, 2025
Vulnerability identifier: #VU114956
CSH Severity: Low
CVSS v4: 8.5 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2025-39727
CWE-ID: CWE-119
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to memory corruption within the setup_clusters() function in mm/swapfile.c. A local user can escalate privileges on the system.
Affected software
Linux kernel
Ubuntu
kernel-rt-debug-modules-extra (Red Hat package)
kernel-rt-modules-core (Red Hat package)
kernel-rt-64k-modules-extra (Red Hat package)
kernel-rt-modules (Red Hat package)
kernel-rt-debug-modules (Red Hat package)
linux (Ubuntu package)
linux-oem-6.14 (Ubuntu package)
linux-realtime-6.14 (Ubuntu package)
linux-azure (Ubuntu package)
linux-aws-6.14 (Ubuntu package)
linux-gcp-6.14 (Ubuntu package)
Ubuntu
kernel-rt-debug-modules-extra (Red Hat package)
kernel-rt-modules-core (Red Hat package)
kernel-rt-64k-modules-extra (Red Hat package)
kernel-rt-modules (Red Hat package)
kernel-rt-debug-modules (Red Hat package)
linux (Ubuntu package)
linux-oem-6.14 (Ubuntu package)
linux-realtime-6.14 (Ubuntu package)
linux-azure (Ubuntu package)
linux-aws-6.14 (Ubuntu package)
linux-gcp-6.14 (Ubuntu package)
How to mitigate CVE-2025-39727
Install update from vendor's repository.
kernel-rt-debug-modules-extra (Red Hat package) - update to 6.12.0-124.9.1.el10_1
kernel-rt-modules-core (Red Hat package) - update to 6.12.0-124.9.1.el10_1
kernel-rt-64k-modules-extra (Red Hat package) - update to 6.12.0-124.9.1.el10_1
kernel-rt-modules (Red Hat package) - update to 6.12.0-124.9.1.el10_1
kernel-rt-debug-modules (Red Hat package) - update to 6.12.0-124.9.1.el10_1
linux (Ubuntu package) - addressed in versions 6.14.0-36.36, 6.14.0-36.36~24.04.1, 6.14.0-1016.16~24.04.1, 6.14.0-1017.17, 6.14.0-1020.21
linux-oem-6.14 (Ubuntu package) - update to 6.14.0-1016.16
linux-realtime-6.14 (Ubuntu package) - update to 6.14.0-1016.16~24.04.1
linux-azure (Ubuntu package) - addressed in versions 6.14.0-1017.17, 6.14.0-1017.17~24.04.1
linux-aws-6.14 (Ubuntu package) - update to 6.14.0-1017.17~24.04.1
linux-gcp-6.14 (Ubuntu package) - addressed in versions 6.14.0-1018.18, 6.14.0-1020.21~24.04.1
kernel-rt-modules-core (Red Hat package) - update to 6.12.0-124.9.1.el10_1
kernel-rt-64k-modules-extra (Red Hat package) - update to 6.12.0-124.9.1.el10_1
kernel-rt-modules (Red Hat package) - update to 6.12.0-124.9.1.el10_1
kernel-rt-debug-modules (Red Hat package) - update to 6.12.0-124.9.1.el10_1
linux (Ubuntu package) - addressed in versions 6.14.0-36.36, 6.14.0-36.36~24.04.1, 6.14.0-1016.16~24.04.1, 6.14.0-1017.17, 6.14.0-1020.21
linux-oem-6.14 (Ubuntu package) - update to 6.14.0-1016.16
linux-realtime-6.14 (Ubuntu package) - update to 6.14.0-1016.16~24.04.1
linux-azure (Ubuntu package) - addressed in versions 6.14.0-1017.17, 6.14.0-1017.17~24.04.1
linux-aws-6.14 (Ubuntu package) - update to 6.14.0-1017.17~24.04.1
linux-gcp-6.14 (Ubuntu package) - addressed in versions 6.14.0-1018.18, 6.14.0-1020.21~24.04.1