{"id":"CVE-2026-53228","summary":"ipv6: sit: reload inner IPv6 header after GSO offloads","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nipv6: sit: reload inner IPv6 header after GSO offloads\n\nipip6_tunnel_xmit() caches the inner IPv6 header pointer at function\nentry and continues using it after iptunnel_handle_offloads().\n\nFor GSO skbs, iptunnel_handle_offloads() calls skb_header_unclone().\nWhen the skb header is cloned, skb_header_unclone() can call\npskb_expand_head(), which may move the skb head. The pskb_expand_head()\ncontract requires pointers into the skb header to be reloaded after the\ncall.\n\nIf the later skb_realloc_headroom() branch is not taken, SIT uses the\nstale iph6 pointer to read the inner hop limit and DS field. That can\nread from a freed skb head after the old head's remaining clone is\nreleased.\n\nReload iph6 after the offload helper succeeds and before subsequent\nreads from the inner IPv6 header. Keep the existing reload after\nskb_realloc_headroom(), since that branch can also replace the skb.","modified":"2026-07-08T08:07:24.595161826Z","published":"2026-06-25T08:39:27.893Z","related":["CGA-j74c-7j98-m8qf"],"database_specific":{"cna_assigner":"Linux","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53228.json"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/0bfa7bba1f41aaf5f0604dc712bb4701493e3aa0"},{"type":"WEB","url":"https://git.kernel.org/stable/c/1132e5edc2866c3530be17622153a597095f0e43"},{"type":"WEB","url":"https://git.kernel.org/stable/c/2fa49b2715e1bad12ce3b0fa64e234d9582c8193"},{"type":"WEB","url":"https://git.kernel.org/stable/c/59f80c919713250fe5d25a4d9aea4e49580fa1d4"},{"type":"WEB","url":"https://git.kernel.org/stable/c/9c67b44edb3598d234efae6e44649eb993c03da5"},{"type":"WEB","url":"https://git.kernel.org/stable/c/cb658c2f5f7977c2a1c77c9f239f4bc8196edb5c"},{"type":"WEB","url":"https://git.kernel.org/stable/c/f0e42f0c4337b1f220de1ddd63f47197c7dee4de"},{"type":"WEB","url":"https://git.kernel.org/stable/c/fddd41445a0537b093e6b3f6232c9933cad1e48b"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/53xxx/CVE-2026-53228.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-53228"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"14909664e4e192f4c6f6fcdccd9919af7cf783ab"},{"fixed":"fddd41445a0537b093e6b3f6232c9933cad1e48b"},{"fixed":"1132e5edc2866c3530be17622153a597095f0e43"},{"fixed":"9c67b44edb3598d234efae6e44649eb993c03da5"},{"fixed":"0bfa7bba1f41aaf5f0604dc712bb4701493e3aa0"},{"fixed":"59f80c919713250fe5d25a4d9aea4e49580fa1d4"},{"fixed":"2fa49b2715e1bad12ce3b0fa64e234d9582c8193"},{"fixed":"cb658c2f5f7977c2a1c77c9f239f4bc8196edb5c"},{"fixed":"f0e42f0c4337b1f220de1ddd63f47197c7dee4de"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-53228.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"3.18.0"},{"fixed":"5.10.259"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.210"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.176"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.143"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.94"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.36"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.0.13"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-53228.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"}]}