{"id":"CVE-2026-63992","revision":"1e07dff77e4a4bdda371c3884c9b4033","records":[{"revision":"1e07dff77e4a4bdda371c3884c9b4033","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-63992","aliases":[],"title":"tunnels: do not assume transport header in iptunnel_pmtud_check_icmp()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ntunnels: do not assume transport header in iptunnel_pmtud_check_icmp()\n\nIn some cases, iptunnel_pmtud_check_icmp() can be called while\nskb transport header is not set.\n\nThis triggers an out-of-bound access, because\n(typeof(skb->transport_header))~0U is 65535.\n\nAccess the icmp header based on IPv4 network header,\nafter making sure icmp->type is present in skb linear part.\n\nNote that iptunnel_pmtud_check_icmpv6()) is fine.","state":0,"publishedAt":"2026-07-19T14:56:12.528+00:00","modifiedAt":"2026-10-19T20:18:01.188+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/ipv4/ip_tunnel_core.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"4cb47a8644cc9eb8ec81190a50e79e6530d0297f\",\n                            \"lessThan\": \"5a92cb45e34749865d03daf8d3500f77b5f6644c\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"4cb47a8644cc9eb8ec81190a50e79e6530d0297f\",\n                            \"lessThan\": \"c7b7ec3e69e673c0d6b57f74d21da50c485c598e\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"4cb47a8644cc9eb8ec81190a50e79e6530d0297f\",\n                            \"lessThan\": \"7f4f7efe7f30edd29c4988de01728bf2398217e4\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"4cb47a8644cc9eb8ec81190a50e79e6530d0297f\",\n                            \"lessThan\": \"e917d0c69f01af2bb4fbea2b66d560a53b3ac7ec\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"4cb47a8644cc9eb8ec81190a50e79e6530d0297f\",\n                            \"lessThan\": \"a096b6e34f602950af9a2b0856cd93a5f4c276d7\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"4cb47a8644cc9eb8ec81190a50e79e6530d0297f\",\n                            \"lessThan\": \"43368636c663cff6e59dde93cf4b8e43ac28eb93\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"4cb47a8644cc9eb8ec81190a50e79e6530d0297f\",\n                            \"lessThan\": \"cb549df9ce4ee15c9d5b19ddab12cf2128e4313c\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"4cb47a8644cc9eb8ec81190a50e79e6530d0297f\",\n                            \"lessThan\": \"509323077ef79a26ba0c60bb556e45c12c398b2d\",\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/ipv4/ip_tunnel_core.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"5.9\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"5.9\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.10.259\",\n                            \"lessThanOrEqual\": \"5.10.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.15.210\",\n                            \"lessThanOrEqual\": \"5.15.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.1.176\",\n                            \"lessThanOrEqual\": \"6.1.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.6.143\",\n                            \"lessThanOrEqual\": \"6.6.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.12.93\",\n                            \"lessThanOrEqual\": \"6.12.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.18.35\",\n                            \"lessThanOrEqual\": \"6.18.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.0.12\",\n                            \"lessThanOrEqual\": \"7.0.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.1\",\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:U/C:H/I:N/A:H","score":9.1,"severity":"CRITICAL"}],"references":["https://git.kernel.org/stable/c/5a92cb45e34749865d03daf8d3500f77b5f6644c","https://git.kernel.org/stable/c/c7b7ec3e69e673c0d6b57f74d21da50c485c598e","https://git.kernel.org/stable/c/7f4f7efe7f30edd29c4988de01728bf2398217e4","https://git.kernel.org/stable/c/e917d0c69f01af2bb4fbea2b66d560a53b3ac7ec","https://git.kernel.org/stable/c/a096b6e34f602950af9a2b0856cd93a5f4c276d7","https://git.kernel.org/stable/c/43368636c663cff6e59dde93cf4b8e43ac28eb93","https://git.kernel.org/stable/c/cb549df9ce4ee15c9d5b19ddab12cf2128e4313c","https://git.kernel.org/stable/c/509323077ef79a26ba0c60bb556e45c12c398b2d"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-63992","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-63992","identifiers":["CVE-2026-63992"]},"retained":false,"historicalAffected":[]}],"coverage":[]}