CVE Catalog

CVE-2026-23391

HighCVSS 7.8
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.12%

2th percentile - higher than 2% of all known CVEs

Summary

A vulnerability was found in the Linux kernel's netfilter xt_CT module, where templates can be removed while packets are still pending in the nfqueue. This can cause issues on helper module removal or timeout policy deletion. The patch flushes these enqueued packets when the template rule is removed.

Risk Assessment

The risk involves potential system instability or memory leaks when packets referencing removed objects (helper, timeout policy) remain queued. This could lead to unpredictable firewall behavior or system crashes.

Recommendation

Immediately update the Linux kernel to a version containing the fix (commit 2e4b8e8c8f9a). Monitor for netfilter and xt_CT related error messages.

Other vulnerabilities in Linux kernel

See all
Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: netfilter: xt_CT: drop pending enqueued packets on template removal Templates refer to objects that can go away while packets are sitting in nfqueue refer to: - helper, this can be an issue on module removal. - timeout policy, nfnetlink_cttimeout might remove it. The use of templates with zone and event cache filter are safe, since this just copies values. Flush these enqueued packets in case the template rule gets removed.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS