{"id":"CVE-2025-22021","revision":"29341cb6db4a4f07abba9c0424eb3041","records":[{"revision":"29341cb6db4a4f07abba9c0424eb3041","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2025-22021","aliases":[],"title":"netfilter: socket: Lookup orig tuple for IPv6 SNAT","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: socket: Lookup orig tuple for IPv6 SNAT\n\nnf_sk_lookup_slow_v4 does the conntrack lookup for IPv4 packets to\nrestore the original 5-tuple in case of SNAT, to be able to find the\nright socket (if any). Then socket_match() can correctly check whether\nthe socket was transparent.\n\nHowever, the IPv6 counterpart (nf_sk_lookup_slow_v6) lacks this\nconntrack lookup, making xt_socket fail to match on the socket when the\npacket was SNATed. Add the same logic to nf_sk_lookup_slow_v6.\n\nIPv6 SNAT is used in Kubernetes clusters for pod-to-world packets, as\npods' addresses are in the fd00::/8 ULA subnet and need to be replaced\nwith the node's external address. Cilium leverages Envoy to enforce L7\npolicies, and Envoy uses transparent sockets. Cilium inserts an iptables\nprerouting rule that matches on `-m socket --transparent` and redirects\nthe packets to localhost, but it fails to match SNATed IPv6 packets due\nto that missing conntrack lookup.","state":0,"publishedAt":"2025-04-16T10:20:37.695+00:00","modifiedAt":"2026-10-15T21:51:56.689+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"net/ipv6/netfilter/nf_socket_ipv6.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"eb31628e37a0a4e01fffd79dcc7f815d2357f53a\",\n                            \"lessThan\": \"6488b96a79a26e19100ad872622f04e93b638d7f\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"eb31628e37a0a4e01fffd79dcc7f815d2357f53a\",\n                            \"lessThan\": \"58ab63d3ded2ca6141357a2b24eee8453d0f871d\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"eb31628e37a0a4e01fffd79dcc7f815d2357f53a\",\n                            \"lessThan\": \"1ca2169cc19dca893c7aae6af122852097435d16\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"eb31628e37a0a4e01fffd79dcc7f815d2357f53a\",\n                            \"lessThan\": \"1ec43100f7123010730b7ddfc3d5c2eac19e70e7\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"eb31628e37a0a4e01fffd79dcc7f815d2357f53a\",\n                            \"lessThan\": \"5251041573850e5020cd447374e23010be698898\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"eb31628e37a0a4e01fffd79dcc7f815d2357f53a\",\n                            \"lessThan\": \"2bb139e483f8cbe488d19d8c1135ac3615e2668c\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"eb31628e37a0a4e01fffd79dcc7f815d2357f53a\",\n                            \"lessThan\": \"41904cbb343d115931d6bf79aa2c815cac4ef72b\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"eb31628e37a0a4e01fffd79dcc7f815d2357f53a\",\n                            \"lessThan\": \"221c27259324ec1404f028d4f5a0f2ae7f63ee23\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"eb31628e37a0a4e01fffd79dcc7f815d2357f53a\",\n                            \"lessThan\": \"932b32ffd7604fb00b5c57e239a3cc4d901ccf6e\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"affected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"net/ipv6/netfilter/nf_socket_ipv6.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"3.13\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"3.13\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.4.292\",\n                            \"lessThanOrEqual\": \"5.4.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.10.236\",\n                            \"lessThanOrEqual\": \"5.10.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.15.180\",\n                            \"lessThanOrEqual\": \"5.15.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.1.133\",\n                            \"lessThanOrEqual\": \"6.1.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.6.86\",\n                            \"lessThanOrEqual\": \"6.6.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.12.22\",\n                            \"lessThanOrEqual\": \"6.12.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.13.10\",\n                            \"lessThanOrEqual\": \"6.13.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.14.1\",\n                            \"lessThanOrEqual\": \"6.14.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.15\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H","score":10,"severity":"CRITICAL"}],"references":["https://git.kernel.org/stable/c/6488b96a79a26e19100ad872622f04e93b638d7f","https://git.kernel.org/stable/c/58ab63d3ded2ca6141357a2b24eee8453d0f871d","https://git.kernel.org/stable/c/1ca2169cc19dca893c7aae6af122852097435d16","https://git.kernel.org/stable/c/1ec43100f7123010730b7ddfc3d5c2eac19e70e7","https://git.kernel.org/stable/c/5251041573850e5020cd447374e23010be698898","https://git.kernel.org/stable/c/2bb139e483f8cbe488d19d8c1135ac3615e2668c","https://git.kernel.org/stable/c/41904cbb343d115931d6bf79aa2c815cac4ef72b","https://git.kernel.org/stable/c/221c27259324ec1404f028d4f5a0f2ae7f63ee23","https://git.kernel.org/stable/c/932b32ffd7604fb00b5c57e239a3cc4d901ccf6e"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2025-22021","license":"CVE Program Terms of Use","key":"cve-program:CVE-2025-22021","identifiers":["CVE-2025-22021"]},"retained":false,"historicalAffected":[]}],"coverage":[]}