CVE-2025-40133

CVE-2025-40133 is a security vulnerability that is still awaiting full analysis and scoring. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Description

In the Linux kernel, the following vulnerability has been resolved: mptcp: Use __sk_dst_get() and dst_dev_rcu() in mptcp_active_enable(). mptcp_active_enable() is called from subflow_finish_connect(), which is icsk->icsk_af_ops->sk_rx_dst_set() and it's not always under RCU. Using sk_dst_get(sk)->dev could trigger UAF. Let's use __sk_dst_get() and dst_dev_rcu().

Frequently asked questions

What is CVE-2025-40133?
In the Linux kernel, the following vulnerability has been resolved: mptcp: Use __sk_dst_get() and dst_dev_rcu() in mptcp_active_enable(). mptcp_active_enable() is called from subflow_finish_connect(), which is icsk->icsk_af_ops->sk_rx_dst_set() and it's not always under RCU. Using sk_dst_get(sk)->dev could trigger UAF. Let's use __sk_dst_get() and dst_dev_rcu().
Is CVE-2025-40133 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (7th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2025-40133?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-40133 have an EU (EUVD) identifier?
Yes. CVE-2025-40133 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-124950.
When was CVE-2025-40133 published?
CVE-2025-40133 was published on 2025-11-12 and last updated on 2026-06-17.

References