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
5.5EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 5.5Exploit: None knownExposed: 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)
EG Risk
29(Track)
EG Risk 29/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity55% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
3%
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.

Patch Availability(1)

Vendor / EcosystemFixed in / PatchReleasedSource
linuxKernel @ 5.10.258—osv

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 7× in last 7d / 39× 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.

Showing the most recent 100 of 104 total refreshes for this CVE.

  1. 2026-07-27 14:13 UTCEPSS rescore
  2. 2026-07-25 14:18 UTCEPSS rescore
  3. 2026-07-24 14:17 UTCEPSS rescore
  4. 2026-07-23 14:18 UTCEPSS rescore
  5. 2026-07-23 03:16 UTCEG score recompute
  6. 2026-07-22 14:08 UTCEPSS rescore
  7. 2026-07-21 15:24 UTCEPSS rescore
  8. 2026-07-20 17:08 UTCEPSS rescore
  9. 2026-07-19 14:31 UTCEPSS rescore
  10. 2026-07-19 04:52 UTCOSV refresh
  11. 2026-07-19 02:29 UTCEPSS rescore
  12. 2026-07-18 10:04 UTCEPSS rescore
  13. 2026-07-16 17:03 UTCEPSS rescore
  14. 2026-07-15 16:57 UTCEPSS rescore
  15. 2026-07-15 02:00 UTCEPSS rescore
  16. 2026-07-13 22:30 UTCEPSS rescore
  17. 2026-07-13 06:13 UTCEPSS rescore
  18. 2026-07-12 05:46 UTCEPSS rescore
  19. 2026-07-11 08:27 UTCEPSS rescore
  20. 2026-07-09 19:10 UTCEPSS rescore
  21. 2026-07-08 15:16 UTCEPSS rescore
  22. 2026-07-07 13:46 UTCEPSS rescore
  23. 2026-07-06 16:27 UTCEPSS rescore
  24. 2026-07-06 02:23 UTCEPSS rescore
  25. 2026-07-05 02:30 UTCEPSS rescore
Show 75 more
  1. 2026-07-04 06:31 UTCEPSS rescore
  2. 2026-07-01 15:07 UTCEPSS rescore
  3. 2026-07-01 11:41 UTCVendor advisory
  4. 2026-07-01 11:41 UTCGHSA enrichment
  5. 2026-06-30 23:22 UTCEPSS rescore
  6. 2026-06-30 05:59 UTCVendor advisory
  7. 2026-06-30 05:59 UTCGHSA enrichment
  8. 2026-06-29 14:06 UTCEPSS rescore
  9. 2026-06-29 14:06 UTCEPSS rescore
  10. 2026-06-28 23:42 UTCVendor advisory
  11. 2026-06-28 23:42 UTCGHSA enrichment
  12. 2026-06-28 14:07 UTCEPSS rescore
  13. 2026-06-28 04:56 UTCEPSS rescore
  14. 2026-06-28 04:56 UTCEPSS rescore
  15. 2026-06-27 22:26 UTCEG score recompute▲ 5.50
  16. 2026-06-27 22:26 UTCVendor advisory
  17. 2026-06-27 22:26 UTCGHSA enrichment
  18. 2026-06-27 03:08 UTCEPSS rescore
  19. 2026-06-26 19:41 UTCNVD updateCVSS v3 → 5.5 · severity → MEDIUM
  20. 2026-06-25 13:49 UTCEPSS rescore
  21. 2026-06-25 02:16 UTCVendor advisory
  22. 2026-06-25 02:16 UTCGHSA enrichment
  23. 2026-06-24 14:05 UTCEPSS rescore
  24. 2026-06-23 21:33 UTCEPSS rescore
  25. 2026-06-23 21:33 UTCEPSS rescore
  26. 2026-06-22 14:25 UTCEPSS rescore
  27. 2026-06-22 14:25 UTCEPSS rescore
  28. 2026-06-21 14:56 UTCEPSS rescore
  29. 2026-06-21 14:56 UTCEPSS rescore
  30. 2026-06-21 01:59 UTCEPSS rescore
  31. 2026-06-21 01:59 UTCEPSS rescore
  32. 2026-06-19 19:26 UTCEPSS rescore
  33. 2026-06-19 19:26 UTCEPSS rescore
  34. 2026-06-18 17:52 UTCEPSS rescore
  35. 2026-06-18 17:52 UTCEPSS rescore
  36. 2026-06-18 02:47 UTCGHSA enrichment
  37. 2026-06-17 17:53 UTCEPSS rescore
  38. 2026-06-15 17:49 UTCEPSS rescore
  39. 2026-06-15 06:37 UTCVendor advisory
  40. 2026-06-15 06:37 UTCGHSA enrichment
  41. 2026-06-14 23:28 UTCMITRE cvelistV5
  42. 2026-06-13 23:00 UTCEPSS rescore
  43. 2026-06-12 23:12 UTCEPSS rescore
  44. 2026-06-12 23:12 UTCEPSS rescore
  45. 2026-06-12 10:26 UTCVendor advisory
  46. 2026-06-12 10:26 UTCGHSA enrichment
  47. 2026-06-11 14:00 UTCEPSS rescore
  48. 2026-06-10 22:18 UTCEPSS rescore
  49. 2026-06-10 13:22 UTCEPSS rescore
  50. 2026-06-10 13:22 UTCEPSS rescore
  51. 2026-06-09 14:17 UTCGHSA enrichment
  52. 2026-06-08 14:17 UTCEPSS rescore
  53. 2026-06-08 14:17 UTCEPSS rescore
  54. 2026-06-07 15:25 UTCEPSS rescore
  55. 2026-06-07 15:25 UTCEPSS rescore
  56. 2026-06-06 18:07 UTCGHSA enrichment
  57. 2026-06-06 13:47 UTCEPSS rescore
  58. 2026-06-06 13:47 UTCEPSS rescore
  59. 2026-06-05 22:47 UTCEPSS rescore
  60. 2026-06-05 06:10 UTCEPSS rescore
  61. 2026-06-05 06:10 UTCEPSS rescore
  62. 2026-06-04 13:12 UTCEPSS rescore
  63. 2026-06-04 13:12 UTCEPSS rescore
  64. 2026-06-03 21:57 UTCGHSA enrichment
  65. 2026-06-02 20:13 UTCEPSS rescore
  66. 2026-06-01 13:52 UTCEPSS rescore
  67. 2026-06-01 13:52 UTCEPSS rescore
  68. 2026-06-01 01:47 UTCGHSA enrichment
  69. 2026-05-31 22:30 UTCEPSS rescore
  70. 2026-05-31 22:30 UTCEPSS rescore
  71. 2026-05-31 00:16 UTCEPSS rescore
  72. 2026-05-31 00:16 UTCEPSS rescore
  73. 2026-05-29 13:44 UTCEPSS rescore
  74. 2026-05-29 13:44 UTCEPSS rescore
  75. 2026-05-28 13:44 UTCEPSS rescore

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 0% probability of exploitation in the next 30 days, which ranks it in the top 97.3% of all scored CVEs.
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.

Dependency Blast Radius

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