CVE-2025-40133
kernel: mptcp: Use __sk_dst_get() and dst_dev_rcu() in mptcp_active_enable()
Severity
ModerateRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · November 12, 2025
Updated · July 30, 2026
Description
A use-after-free flaw was found in Multipath TCP in the Linux kernel in net/mptcp/ctrl.c:mptcp_active_enablecode due to concurrency problem. This flaw could allow an attacker to crash the system at device disconnect. This vulnerability could even lead to a kernel information leak problem.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
CVSS / CWE
CVSS 3.1 · 7CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
CWE-825 · Expired Pointer Dereference