CVE Catalog

CVE-2026-100070

Unknown
Published: Translated: NVD NIST

Summary

In the Linux kernel, a bug in the netfilter nf_nat_sip module was fixed where the offset was not rewound when NAT shrinks the packet. If map_addr() changes the packet length, coff may point to an incorrect position, potentially causing subsequent Contact headers to be skipped and leaking internal network details.

Risk Assessment

Internal network details may leak through improper SIP header processing. This affects systems using NAT for SIP with the nf_nat_sip module.

Recommendation

Update the Linux kernel to a version containing the fix. Consider additional SIP-level protections if possible.

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: nf_nat_sip: rewind offset when NAT shrinks the packet sashiko says: If map_addr() changes the packet length, such as when the public NAT IP string is shorter or longer than the internal IP, coff will still point to the offset relative to the pre-mangled packet. If the packet shrinks, coff could overshoot the correct position, potentially causing the next ct_sip_parse_header_uri() call to silently skip bytes and miss subsequent Contact headers. Could this lead to a failure to NAT those subsequent headers and leak internal network details?

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