{"id":"CVE-2025-71098","summary":"ip6_gre: make ip6gre_header() robust","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nip6_gre: make ip6gre_header() robust\n\nOver the years, syzbot found many ways to crash the kernel\nin ip6gre_header() [1].\n\nThis involves team or bonding drivers ability to dynamically\nchange their dev-\u003eneeded_headroom and/or dev-\u003ehard_header_len\n\nIn this particular crash mld_newpack() allocated an skb\nwith a too small reserve/headroom, and by the time mld_sendpack()\nwas called, syzbot managed to attach an ip6gre device.\n\n[1]\nskbuff: skb_under_panic: text:ffffffff8a1d69a8 len:136 put:40 head:ffff888059bc7000 data:ffff888059bc6fe8 tail:0x70 end:0x6c0 dev:team0\n------------[ cut here ]------------\n kernel BUG at net/core/skbuff.c:213 !\n \u003cTASK\u003e\n  skb_under_panic net/core/skbuff.c:223 [inline]\n  skb_push+0xc3/0xe0 net/core/skbuff.c:2641\n  ip6gre_header+0xc8/0x790 net/ipv6/ip6_gre.c:1371\n  dev_hard_header include/linux/netdevice.h:3436 [inline]\n  neigh_connected_output+0x286/0x460 net/core/neighbour.c:1618\n  neigh_output include/net/neighbour.h:556 [inline]\n  ip6_finish_output2+0xfb3/0x1480 net/ipv6/ip6_output.c:136\n __ip6_finish_output net/ipv6/ip6_output.c:-1 [inline]\n  ip6_finish_output+0x234/0x7d0 net/ipv6/ip6_output.c:220\n  NF_HOOK_COND include/linux/netfilter.h:307 [inline]\n  ip6_output+0x340/0x550 net/ipv6/ip6_output.c:247\n  NF_HOOK+0x9e/0x380 include/linux/netfilter.h:318\n  mld_sendpack+0x8d4/0xe60 net/ipv6/mcast.c:1855\n  mld_send_cr net/ipv6/mcast.c:2154 [inline]\n  mld_ifc_work+0x83e/0xd60 net/ipv6/mcast.c:2693","modified":"2026-04-02T13:04:47.723890Z","published":"2026-01-13T15:34:57.536Z","related":["MGASA-2026-0017","MGASA-2026-0018","SUSE-SU-2026:0447-1","SUSE-SU-2026:0472-1","SUSE-SU-2026:0473-1","SUSE-SU-2026:0587-1","SUSE-SU-2026:20477-1","SUSE-SU-2026:20498-1","SUSE-SU-2026:20555-1","SUSE-SU-2026:20599-1","SUSE-SU-2026:20615-1","SUSE-SU-2026:20845-1","SUSE-SU-2026:20876-1","openSUSE-SU-2026:20287-1"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/71xxx/CVE-2025-71098.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/1717357007db150c2d703f13f5695460e960f26c"},{"type":"WEB","url":"https://git.kernel.org/stable/c/17e7386234f740f3e7d5e58a47b5847ea34c3bc2"},{"type":"WEB","url":"https://git.kernel.org/stable/c/41a1a3140aff295dee8063906f70a514548105e8"},{"type":"WEB","url":"https://git.kernel.org/stable/c/5fe210533e3459197eabfdbf97327dacbdc04d60"},{"type":"WEB","url":"https://git.kernel.org/stable/c/91a2b25be07ce1a7549ceebbe82017551d2eec92"},{"type":"WEB","url":"https://git.kernel.org/stable/c/adee129db814474f2f81207bd182bf343832a52e"},{"type":"WEB","url":"https://git.kernel.org/stable/c/db5b4e39c4e63700c68a7e65fc4e1f1375273476"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/71xxx/CVE-2025-71098.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-71098"},{"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":"c12b395a46646bab69089ce7016ac78177f6001f"},{"fixed":"17e7386234f740f3e7d5e58a47b5847ea34c3bc2"},{"fixed":"41a1a3140aff295dee8063906f70a514548105e8"},{"fixed":"adee129db814474f2f81207bd182bf343832a52e"},{"fixed":"1717357007db150c2d703f13f5695460e960f26c"},{"fixed":"5fe210533e3459197eabfdbf97327dacbdc04d60"},{"fixed":"91a2b25be07ce1a7549ceebbe82017551d2eec92"},{"fixed":"db5b4e39c4e63700c68a7e65fc4e1f1375273476"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-71098.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"3.7.0"},{"fixed":"5.10.248"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.198"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.160"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.120"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.64"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.4"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-71098.json"}}],"schema_version":"1.7.5"}