CVE-2025-38491 — Improper Locking in Linux

CWE-667 — Improper LockingCWE-366 — Race Condition within a Thread48 documents8 sources
Severity
5.5MEDIUMNVD
OSV3.2
EPSS
0.0%
top 93.65%
CISA KEV
Not in KEV
Exploit
No known exploits
Affected products
3
LinuxLinux KernelDebian Linux
Timeline
PublishedJul 28
Latest updateMar 25

Description

In the Linux kernel, the following vulnerability has been resolved: mptcp: make fallback action and fallback decision atomic Syzkaller reported the following splat: WARNING: CPU: 1 PID: 7704 at net/mptcp/protocol.h:1223 __mptcp_do_fallback net/mptcp/protocol.h:1223 [inline] WARNING: CPU: 1 PID: 7704 at net/mptcp/protocol.h:1223 mptcp_do_fallback net/mptcp/protocol.h:1244 [inline] WARNING: CPU: 1 PID: 7704 at net/mptcp/protocol.h:1223 check_fully_established net/mptcp/options.c:982 [inline] WA…

CVSS vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:HExploitability: 1.8 | Impact: 3.6

Affected Packages4 packages

▶NVDlinux/linux_kernel5.10.228 — 5.11+6
▶Debianlinux/linux_kernel< 6.1.153-1+2
▶Ubuntulinux/linux_kernel< 6.8.0-100.100
▶CVEListV5linux/linux0530020a7c8f2204e784f0dbdc882bbd961fdbde — 5586518bec27666c747cd52aabb62d485686d0bf+7

Also affects: Debian Linux 11.0

Patches

Patch: git.kernel.org ↗Patch: git.kernel.org ↗Patch: git.kernel.org ↗

🔴Vulnerability Details

25
OSV
linux-azure-6.8 vulnerabilities↗2026-03-25
▶
OSV
linux-azure-fips vulnerabilities↗2026-03-04
▶
OSV
linux-azure vulnerabilities↗2026-03-04
▶
OSV
linux-ibm, linux-ibm-6.8 vulnerabilities↗2026-02-24
▶
OSV
linux-xilinx vulnerabilities↗2026-02-24
▶

📋Vendor Advisories

22
Ubuntu
Linux kernel (Azure) vulnerabilities↗2026-03-25
▶
Ubuntu
Linux kernel (Azure) vulnerabilities↗2026-03-04
▶
Ubuntu
Linux kernel (Azure FIPS) vulnerabilities↗2026-03-04
▶
Ubuntu
Linux kernel (Xilinx) vulnerabilities↗2026-02-24
▶
Ubuntu
Linux kernel (IBM) vulnerabilities↗2026-02-24
▶
CVE-2025-38491 — Improper Locking in Linux | cvebase