{"id":"CVE-2026-45841","title":"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->window % f->wss.val in the\nOSF_WSS_MODULO branch with no guard for f->w…","summary":"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->window % f->wss.val in the\nOSF_WSS_MODULO branch with no guard for f->w…","severity":"medium","cvss":5.5,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","cwe":["CWE-369"],"vendor":"linux","product":"linux_kernel","affected":["linux_kernel >= 2.6.31, < 5.10.258","linux_kernel >= 5.11, < 5.15.209","linux_kernel >= 5.16, < 6.1.175","linux_kernel >= 6.2, < 6.6.141","linux_kernel >= 6.7, < 6.12.91","linux_kernel >= 6.13, < 6.18.33","linux_kernel >= 6.19, < 7.0.10"],"patched":["linux_kernel 7.0.10"],"published":"2026-05-27","updated":"2026-09-08","sourceUpdated":"2026-09-08T09:18:06.090","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-45841","references":[{"url":"https://git.kernel.org/stable/c/0694618cf3e9b120666e31f5f383a6e466d95a0d","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/2195574dc6d9017d32ac346987e12659f931d932","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/26900306a5a2c3e4f75c643a064525526bb6e5f3","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/8def8fbd23f40e945febe913d04b731012ce0082","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/9a05e195618a6d474f2bcd5b6376d0ffc2f00366","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/c55940895245d8ef658ab381248a28755218d625","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/cb833bbc1b3c51e08652d3c86298307c07d3f2db","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/fb965b1cfe92b28d28b5ebe3116b81dbef9f2d2f","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://cert-portal.siemens.com/productcert/html/ssa-019113.html","label":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"}],"tags":["nvd","cve.org"],"epss":0.00129,"epssPercentile":0.02966,"ingestedAt":"2026-09-08T13:33:24.148Z","slug":"CVE-2026-45841","body":"## Overview\n\nIn 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->window % f->wss.val in the\nOSF_WSS_MODULO branch with no guard for f->wss.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->wss is per-fingerprint, not per-option, so\nthe check must run regardless of f->opt_num (including 0). Also\nreject wss.wc >= 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 <IRQ>\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)\n\n## Affected\n\n- `linux_kernel >= 2.6.31, < 5.10.258`\n- `linux_kernel >= 5.11, < 5.15.209`\n- `linux_kernel >= 5.16, < 6.1.175`\n- `linux_kernel >= 6.2, < 6.6.141`\n- `linux_kernel >= 6.7, < 6.12.91`\n- `linux_kernel >= 6.13, < 6.18.33`\n- `linux_kernel >= 6.19, < 7.0.10`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `linux_kernel 7.0.10`","depth":"sunlit","depthScore":30,"depthScoreParts":{"impact":30.3,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}