Vulnerability in Linux

CVE-2025-39764

In the Linux kernel, the following vulnerability has been resolved: netfilter: ctnetlink: remove refcounting in expectation dumpers Same pattern as previous patch: do not keep the expectation object alive via refcount, only store a cookie value and then use that as the skip hint for dump resumption. AFAICS this has the same issue as the one resolved in the conntrack dumper, when we do if (!refcount_inc_not_zero(&exp->use)) to increment the refcount, there is a chance that exp == last, which causes a double-increment of the refcount and subsequent memory leak.

EPSS: 0.002 (5.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.5 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.

Affected products

References

Frequently asked questions

What is CVE-2025-39764?
CVE-2025-39764 is a medium-severity vulnerability in Linux. CVSS score: 5.5/10. Published 2025-09-11.
How severe is CVE-2025-39764?
Medium severity. CVSS v3 base score is 5.5 out of 10.