{"id":"CVE-2026-45841","summary":"netfilter: nfnetlink_osf: fix divide-by-zero in OSF_WSS_MODULO","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nfnetlink_osf: fix divide-by-zero in OSF_WSS_MODULO\n\nnf_osf_match_one() computes ctx-\u003ewindow % f-\u003ewss.val in the\nOSF_WSS_MODULO branch with no guard for f-\u003ewss.val == 0. A\nCAP_NET_ADMIN user can add such a fingerprint via nfnetlink; a\nsubsequent matching TCP SYN divides by zero and panics the kernel.\n\nReject the bogus fingerprint in nfnl_osf_add_callback() above the\nper-option for-loop. f-\u003ewss is per-fingerprint, not per-option, so\nthe check must run regardless of f-\u003eopt_num (including 0). Also\nreject wss.wc \u003e= OSF_WSS_MAX; nf_osf_match_one() already treats that\nas \"should not happen\".\n\nCrash:\n Oops: divide error: 0000 [#1] SMP KASAN NOPTI\n RIP: 0010:nf_osf_match_one (net/netfilter/nfnetlink_osf.c:98)\n Call Trace:\n \u003cIRQ\u003e\n  nf_osf_match (net/netfilter/nfnetlink_osf.c:220)\n  xt_osf_match_packet (net/netfilter/xt_osf.c:32)\n  ipt_do_table (net/ipv4/netfilter/ip_tables.c:348)\n  nf_hook_slow (net/netfilter/core.c:622)\n  ip_local_deliver (net/ipv4/ip_input.c:265)\n  ip_rcv (include/linux/skbuff.h:1162)\n  __netif_receive_skb_one_core (net/core/dev.c:6181)\n  process_backlog (net/core/dev.c:6642)\n  __napi_poll (net/core/dev.c:7710)\n  net_rx_action (net/core/dev.c:7945)\n  handle_softirqs (kernel/softirq.c:622)","modified":"2026-07-11T03:54:12.742955624Z","published":"2026-05-27T09:24:40.805Z","related":["SUSE-SU-2026:22433-1","SUSE-SU-2026:22436-1","SUSE-SU-2026:22458-1","SUSE-SU-2026:22460-1","SUSE-SU-2026:2450-1","SUSE-SU-2026:2722-1","SUSE-SU-2026:2799-1","openSUSE-SU-2026:10954-1"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/45xxx/CVE-2026-45841.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/0694618cf3e9b120666e31f5f383a6e466d95a0d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/2195574dc6d9017d32ac346987e12659f931d932"},{"type":"WEB","url":"https://git.kernel.org/stable/c/26900306a5a2c3e4f75c643a064525526bb6e5f3"},{"type":"WEB","url":"https://git.kernel.org/stable/c/8def8fbd23f40e945febe913d04b731012ce0082"},{"type":"WEB","url":"https://git.kernel.org/stable/c/9a05e195618a6d474f2bcd5b6376d0ffc2f00366"},{"type":"WEB","url":"https://git.kernel.org/stable/c/c55940895245d8ef658ab381248a28755218d625"},{"type":"WEB","url":"https://git.kernel.org/stable/c/cb833bbc1b3c51e08652d3c86298307c07d3f2db"},{"type":"WEB","url":"https://git.kernel.org/stable/c/fb965b1cfe92b28d28b5ebe3116b81dbef9f2d2f"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/45xxx/CVE-2026-45841.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-45841"},{"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":"11eeef41d5f63c7d2f7fdfcc733eb7fb137cc384"},{"fixed":"cb833bbc1b3c51e08652d3c86298307c07d3f2db"},{"fixed":"26900306a5a2c3e4f75c643a064525526bb6e5f3"},{"fixed":"0694618cf3e9b120666e31f5f383a6e466d95a0d"},{"fixed":"8def8fbd23f40e945febe913d04b731012ce0082"},{"fixed":"c55940895245d8ef658ab381248a28755218d625"},{"fixed":"fb965b1cfe92b28d28b5ebe3116b81dbef9f2d2f"},{"fixed":"9a05e195618a6d474f2bcd5b6376d0ffc2f00366"},{"fixed":"2195574dc6d9017d32ac346987e12659f931d932"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-45841.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"2.6.31"},{"fixed":"5.10.258"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.209"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.175"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.141"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.91"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.33"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.0.10"}]}],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-45841.json"}}],"schema_version":"1.7.5"}