CVE Catalog

CVE-2026-80664

HighCVSS 7.3
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.13%

3th percentile - higher than 3% of all known CVEs

Summary

In the Linux kernel, netfilter xt_nat SNAT and DNAT target handlers assume IP-family conntrack state and can dereference a NULL pointer when instantiated from an unsupported family through nft_compat. A bridge-family compat rule can trigger a NULL-dereference in nf_nat_setup_info(). The fix rejects non-IP families in xt_nat_checkentry() so unsupported targets cannot be installed, while keeping NFPROTO_INET allowed.

Risk Assessment

The risk is a potential kernel crash (NULL pointer dereference) due to using NAT rules in unsupported families, which could lead to system unavailability.

Recommendation

It is recommended to apply the kernel patch containing this protection to prevent installation of unsupported NAT targets.

Other vulnerabilities in Linux kernel

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Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: netfilter: xt_nat: reject unsupported target families xt_nat SNAT and DNAT target handlers assume IP-family conntrack state is present and can dereference a NULL pointer when instantiated from an unsupported family through nft_compat. A bridge-family compat rule can therefore trigger a NULL-dereference in nf_nat_setup_info(). Reject non-IP families in xt_nat_checkentry() so unsupported targets cannot be installed. Keep NFPROTO_INET allowed for valid inet NAT compat users and leave the runtime fast path unchanged. [ The crash was fixed via 9dbba7e694ec ("netfilter: nft_compat: ebtables emulation must reject non-bridge targets"), so this patch is no longer critical. Nevertheless, NAT is only relevant for ipv4/ipv6, so this extra family check is a good idea in any case. ]

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