CVE-2026-31423

MEDIUMNVD 5.55.5
EchelonGraph scoreMEDIUM confidence

Score 5.5 from GitHub Security Advisory published 2026-04-13. NVD baseline CVSS 5.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
Trending — 3 sources updated this week
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:

net/sched: sch_hfsc: fix divide-by-zero in rtsc_min()

m2sm() converts a u32 slope to a u64 scaled value. For large inputs (e.g. m1=4000000000), the result can reach 2^32. rtsc_min() stores the difference of two such u64 values in a u32 variable dsm and uses it as a divisor. When the difference is exactly 2^32 the truncation yields zero, causing a divide-by-zero oops in the concave-curve intersection path:

Oops: divide error: 0000 RIP: 0010:rtsc_min (net/sched/sch_hfsc.c:601) Call Trace: init_ed (net/sched/sch_hfsc.c:629) hfsc_enqueue (net/sched/sch_hfsc.c:1569) [...]

Widen dsm to u64 and replace do_div() with div64_u64() so the full difference is preserved.

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
2.2%
KEV
Not listed

Published

April 13, 2026

Last Modified

July 14, 2026

Advisory Details (10)

Auto-updated Jul 19, 2026
⚠️ Active exploitation confirmed. No patch confirmed yet.
generic

net/sched: sch_hfsc: fix divide-by-zero in rtsc_min() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/d0aefec1b1a1ba2c1d251028dc2c4e5b4ce1fea5
generic

net/sched: sch_hfsc: fix divide-by-zero in rtsc_min() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/c56f78614e7781aaceca9bd3cb2128bf7d45c3bd
generic

net/sched: sch_hfsc: fix divide-by-zero in rtsc_min() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/b9e6431cbea8bb1fae8069ed099b4ee100499835
generic

net/sched: sch_hfsc: fix divide-by-zero in rtsc_min() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/ad8e8fec40290a8c8cf145c0deaadf76f80c5163
generic

net/sched: sch_hfsc: fix divide-by-zero in rtsc_min() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/ab1ff5890c7354afc7be56502fcfbd61f3b7ae4f
generic

net/sched: sch_hfsc: fix divide-by-zero in rtsc_min() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/4576100b8cd03118267513cafacde164b498b322
generic

net/sched: sch_hfsc: fix divide-by-zero in rtsc_min() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/25b6821884713a31e2b49fb67b0ebd765b33e0a9
generic

net/sched: sch_hfsc: fix divide-by-zero in rtsc_min() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/17c1b9807b8a67d676b6dcf749ee932ebaa7f568

Vendor Advisories for CVE-2026-31423(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 @ 5.10.253osv

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 17× in last 7d / 49× 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 128 total refreshes for this CVE.

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

Frequently asked(5)

What is CVE-2026-31423?
CVE-2026-31423 is a medium vulnerability published on April 13, 2026. In the Linux kernel, the following vulnerability has been resolved: net/sched: schhfsc: fix divide-by-zero in rtscmin() m2sm() converts a u32 slope to a u64 scaled value. For large inputs (e.g. m1=4000000000), the result can reach 2^32. rtsc_min() stores the difference of two such u64 values in a…
When was CVE-2026-31423 disclosed?
CVE-2026-31423 was first published in the National Vulnerability Database on April 13, 2026, with the most recent update on July 14, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-31423 actively exploited?
CVE-2026-31423 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 2.2% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-31423?
CVE-2026-31423 has a CVSS v3 base score of 5.5 (NVD).
How do I remediate CVE-2026-31423?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-31423, 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

Explore the affected products and dependency analysis for CVE-2026-31423

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