CVE-2026-45841

MEDIUMNVD 5.55.5—
EchelonGraph scoreMEDIUM confidence

Score 5.5 from GitHub Security Advisory published 2026-05-27. NVD baseline CVSS 5.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
5.5
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS: 0%CVSS: 5.5Exploit: NoneExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

In the Linux kernel, the following vulnerability has been resolved:

netfilter: nfnetlink_osf: fix divide-by-zero in OSF_WSS_MODULO

nf_osf_match_one() computes ctx->window % f->wss.val in the OSF_WSS_MODULO branch with no guard for f->wss.val == 0. A CAP_NET_ADMIN user can add such a fingerprint via nfnetlink; a subsequent matching TCP SYN divides by zero and panics the kernel.

Reject the bogus fingerprint in nfnl_osf_add_callback() above the per-option for-loop. f->wss is per-fingerprint, not per-option, so the check must run regardless of f->opt_num (including 0). Also reject wss.wc >= OSF_WSS_MAX; nf_osf_match_one() already treats that as "should not happen".

Crash: Oops: divide error: 0000 [#1] SMP KASAN NOPTI RIP: 0010:nf_osf_match_one (net/netfilter/nfnetlink_osf.c:98) Call Trace: nf_osf_match (net/netfilter/nfnetlink_osf.c:220) xt_osf_match_packet (net/netfilter/xt_osf.c:32) ipt_do_table (net/ipv4/netfilter/ip_tables.c:348) nf_hook_slow (net/netfilter/core.c:622) ip_local_deliver (net/ipv4/ip_input.c:265) ip_rcv (include/linux/skbuff.h:1162) __netif_receive_skb_one_core (net/core/dev.c:6181) process_backlog (net/core/dev.c:6642) __napi_poll (net/core/dev.c:7710) net_rx_action (net/core/dev.c:7945) handle_softirqs (kernel/softirq.c:622)

CVSS v3
5.5
EG Score
5.5(medium)
EPSS
1.8%
KEV
Not listed

Published

May 27, 2026

Last Modified

June 26, 2026

Advisory Details (8)

Auto-updated Jun 26, 2026
No patch confirmed yet.
generic

netfilter: nfnetlink_osf: fix divide-by-zero in OSF_WSS_MODULO - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/fb965b1cfe92b28d28b5ebe3116b81dbef9f2d2f
generic

netfilter: nfnetlink_osf: fix divide-by-zero in OSF_WSS_MODULO - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/cb833bbc1b3c51e08652d3c86298307c07d3f2db
generic

netfilter: nfnetlink_osf: fix divide-by-zero in OSF_WSS_MODULO - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/c55940895245d8ef658ab381248a28755218d625
generic

netfilter: nfnetlink_osf: fix divide-by-zero in OSF_WSS_MODULO - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/9a05e195618a6d474f2bcd5b6376d0ffc2f00366
generic

netfilter: nfnetlink_osf: fix divide-by-zero in OSF_WSS_MODULO - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/8def8fbd23f40e945febe913d04b731012ce0082
generic

netfilter: nfnetlink_osf: fix divide-by-zero in OSF_WSS_MODULO - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/26900306a5a2c3e4f75c643a064525526bb6e5f3
generic

netfilter: nfnetlink_osf: fix divide-by-zero in OSF_WSS_MODULO - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/2195574dc6d9017d32ac346987e12659f931d932
generic

netfilter: nfnetlink_osf: fix divide-by-zero in OSF_WSS_MODULO - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/0694618cf3e9b120666e31f5f383a6e466d95a0d

Vendor Advisories for CVE-2026-45841(2)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 7× in last 7d / 52× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-07-15 16:57 UTCEPSS rescore
  2. 2026-07-15 02:00 UTCEPSS rescore
  3. 2026-07-13 22:30 UTCEPSS rescore
  4. 2026-07-13 06:13 UTCEPSS rescore
  5. 2026-07-12 05:46 UTCEPSS rescore
  6. 2026-07-11 08:27 UTCEPSS rescore
  7. 2026-07-09 19:10 UTCEPSS rescore
  8. 2026-07-08 15:16 UTCEPSS rescore
  9. 2026-07-07 13:46 UTCEPSS rescore
  10. 2026-07-06 16:27 UTCEPSS rescore
  11. 2026-07-06 02:23 UTCEPSS rescore
  12. 2026-07-05 02:30 UTCEPSS rescore
  13. 2026-07-04 06:31 UTCEPSS rescore
  14. 2026-07-01 15:07 UTCEPSS rescore
  15. 2026-07-01 11:41 UTCEG score recompute
  16. 2026-07-01 11:41 UTCVendor advisory
  17. 2026-07-01 11:41 UTCGHSA enrichment
  18. 2026-06-30 23:22 UTCEPSS rescore
  19. 2026-06-30 05:59 UTCEG score recompute
  20. 2026-06-30 05:59 UTCVendor advisory
  21. 2026-06-30 05:59 UTCGHSA enrichment
  22. 2026-06-29 14:06 UTCEPSS rescore
  23. 2026-06-29 14:06 UTCEPSS rescore
  24. 2026-06-28 23:42 UTCEG score recompute
  25. 2026-06-28 23:42 UTCVendor advisory
Show 70 more
  1. 2026-06-28 23:42 UTCGHSA enrichment
  2. 2026-06-28 14:07 UTCEPSS rescore
  3. 2026-06-28 04:56 UTCEPSS rescore
  4. 2026-06-28 04:56 UTCEPSS rescore
  5. 2026-06-27 22:26 UTCEG score recompute▲ 5.50
  6. 2026-06-27 22:26 UTCVendor advisory
  7. 2026-06-27 22:26 UTCGHSA enrichment
  8. 2026-06-27 03:08 UTCEPSS rescore
  9. 2026-06-26 19:41 UTCNVD updateCVSS v3 → 5.5 · severity → MEDIUM
  10. 2026-06-25 13:49 UTCEPSS rescore
  11. 2026-06-25 02:16 UTCVendor advisory
  12. 2026-06-25 02:16 UTCGHSA enrichment
  13. 2026-06-24 14:05 UTCEPSS rescore
  14. 2026-06-23 21:33 UTCEPSS rescore
  15. 2026-06-23 21:33 UTCEPSS rescore
  16. 2026-06-22 14:25 UTCEPSS rescore
  17. 2026-06-22 14:25 UTCEPSS rescore
  18. 2026-06-21 14:56 UTCEPSS rescore
  19. 2026-06-21 14:56 UTCEPSS rescore
  20. 2026-06-21 01:59 UTCEPSS rescore
  21. 2026-06-21 01:59 UTCEPSS rescore
  22. 2026-06-19 19:26 UTCEPSS rescore
  23. 2026-06-19 19:26 UTCEPSS rescore
  24. 2026-06-18 17:52 UTCEPSS rescore
  25. 2026-06-18 17:52 UTCEPSS rescore
  26. 2026-06-18 02:47 UTCGHSA enrichment
  27. 2026-06-17 17:53 UTCEPSS rescore
  28. 2026-06-15 17:49 UTCEPSS rescore
  29. 2026-06-15 06:37 UTCVendor advisory
  30. 2026-06-15 06:37 UTCGHSA enrichment
  31. 2026-06-14 23:28 UTCMITRE cvelistV5
  32. 2026-06-13 23:00 UTCEPSS rescore
  33. 2026-06-12 23:12 UTCEPSS rescore
  34. 2026-06-12 23:12 UTCEPSS rescore
  35. 2026-06-12 10:26 UTCVendor advisory
  36. 2026-06-12 10:26 UTCGHSA enrichment
  37. 2026-06-11 14:00 UTCEPSS rescore
  38. 2026-06-10 22:18 UTCEPSS rescore
  39. 2026-06-10 13:22 UTCEPSS rescore
  40. 2026-06-10 13:22 UTCEPSS rescore
  41. 2026-06-09 14:17 UTCGHSA enrichment
  42. 2026-06-08 14:17 UTCEPSS rescore
  43. 2026-06-08 14:17 UTCEPSS rescore
  44. 2026-06-07 15:25 UTCEPSS rescore
  45. 2026-06-07 15:25 UTCEPSS rescore
  46. 2026-06-06 18:07 UTCGHSA enrichment
  47. 2026-06-06 13:47 UTCEPSS rescore
  48. 2026-06-06 13:47 UTCEPSS rescore
  49. 2026-06-05 22:47 UTCEPSS rescore
  50. 2026-06-05 06:10 UTCEPSS rescore
  51. 2026-06-05 06:10 UTCEPSS rescore
  52. 2026-06-04 13:12 UTCEPSS rescore
  53. 2026-06-04 13:12 UTCEPSS rescore
  54. 2026-06-03 21:57 UTCGHSA enrichment
  55. 2026-06-02 20:13 UTCEPSS rescore
  56. 2026-06-01 13:52 UTCEPSS rescore
  57. 2026-06-01 13:52 UTCEPSS rescore
  58. 2026-06-01 01:47 UTCEG score recompute
  59. 2026-06-01 01:47 UTCGHSA enrichment
  60. 2026-05-31 22:30 UTCEPSS rescore
  61. 2026-05-31 22:30 UTCEPSS rescore
  62. 2026-05-31 00:16 UTCEPSS rescore
  63. 2026-05-31 00:16 UTCEPSS rescore
  64. 2026-05-29 13:44 UTCEPSS rescore
  65. 2026-05-29 13:44 UTCEPSS rescore
  66. 2026-05-28 13:44 UTCEPSS rescore
  67. 2026-05-28 13:44 UTCEPSS rescore
  68. 2026-05-27 13:40 UTCEPSS rescore
  69. 2026-05-27 13:40 UTCEPSS rescore
  70. 2026-05-27 10:31 UTCEG score recompute

Frequently asked(5)

What is CVE-2026-45841?
CVE-2026-45841 is a medium vulnerability published on May 27, 2026. In the Linux kernel, the following vulnerability has been resolved: netfilter: nfnetlinkosf: fix divide-by-zero in OSFWSS_MODULO nfosfmatch_one() computes ctx->window % f->wss.val in the OSFWSSMODULO branch with no guard for f->wss.val == 0. A CAPNETADMIN user can add such a fingerprint via…
When was CVE-2026-45841 disclosed?
CVE-2026-45841 was first published in the National Vulnerability Database on May 27, 2026, with the most recent update on June 26, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-45841 actively exploited?
CVE-2026-45841 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 1.8% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-45841?
CVE-2026-45841 has a CVSS v3 base score of 5.5 (NVD).
How do I remediate CVE-2026-45841?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-45841, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

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