CVE-2026-31483

MEDIUMNVD 5.55.5—
EchelonGraph scoreMEDIUM confidence

Score 5.5 from GitHub Security Advisory published 2026-04-22. 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:

s390/syscalls: Add spectre boundary for syscall dispatch table

The s390 syscall number is directly controlled by userspace, but does not have an array_index_nospec() boundary to prevent access past the syscall function pointer tables.

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
2%
KEV
Not listed

Published

April 22, 2026

Last Modified

April 28, 2026

Advisory Details (7)

Auto-updated Aug 2, 2026
No patch confirmed yet.
generic

s390/syscalls: Add spectre boundary for syscall dispatch table - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/f8c444b918d639e1f9a621ee20fe481c1d10dfc4
generic

s390/syscalls: Add spectre boundary for syscall dispatch table - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/87776f02449e3bded95b2ccbd6b012e9ae64e6f3
generic

s390/syscalls: Add spectre boundary for syscall dispatch table - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/7a5260fbc6e79a1595328ec5c6aa3f937504a1f0
generic

s390/syscalls: Add spectre boundary for syscall dispatch table - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/4d05dd18d867d58c6952a3bc260d244899da7256
generic

s390/syscalls: Add spectre boundary for syscall dispatch table - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/48b8814e25d073dd84daf990a879a820bad2bcbd
generic

s390/syscalls: Add spectre boundary for syscall dispatch table - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/3c3b97064764899c39a0abbd35a6caa031e70333
generic

s390/syscalls: Add spectre boundary for syscall dispatch table - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/1cb9c7bc9025c637564fabc7fcc3c9343949e310

Vendor Advisories for CVE-2026-31483(1)

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 @ 5.15.203—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.

Affected Packages

(4 across 4 ecosystems)
Debian:11(1)
PackageVulnerable rangeFixed inDependents
linux-6.16.1.106-3~deb11u1 ... 6.1.164-1~deb11u1 (16 versions)6.1.170-1~deb11u1—
Debian:12(1)
PackageVulnerable rangeFixed inDependents
linux6.1.106-1 ... 6.1.99-1 (48 versions)6.1.170-1—
Debian:13(1)
PackageVulnerable rangeFixed inDependents
linux6.12.38-1 ... 6.12.85-1~bpo12+1 (17 versions)6.12.85-1—
Debian:14(1)
PackageVulnerable rangeFixed inDependents
linux6.12.100-1 ... 6.19~rc8-1~exp1 (124 versions)6.19.11-1—

Additional Vendor Advisories

(24)

Vendors that published advisories for this CVE beyond the curated set above. Broader coverage but minimal per-row detail — click through for the original advisory.

Data Freshness Timeline

(refreshed 5× in last 7d / 29× 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 216 total refreshes for this CVE.

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

Frequently asked(5)

What is CVE-2026-31483?
CVE-2026-31483 is a medium vulnerability published on April 22, 2026. In the Linux kernel, the following vulnerability has been resolved: s390/syscalls: Add spectre boundary for syscall dispatch table The s390 syscall number is directly controlled by userspace, but does not have an arrayindexnospec() boundary to prevent access past the syscall function pointer tables.
When was CVE-2026-31483 disclosed?
CVE-2026-31483 was first published in the National Vulnerability Database on April 22, 2026, with the most recent update on April 28, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-31483 actively exploited?
CVE-2026-31483 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 97.7% of all scored CVEs.
What is the CVSS score of CVE-2026-31483?
CVE-2026-31483 has a CVSS v3 base score of 5.5 (NVD).
How do I remediate CVE-2026-31483?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-31483, 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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