CVE-2026-31773

HIGHNVD 8.88.8
EchelonGraph scoreMEDIUM confidence

Score 8.8 from GitHub Security Advisory (severity: HIGH) published 2026-05-01. NVD baseline CVSS 8.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
8.8EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 8.8Exploit: 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:

Bluetooth: SMP: derive legacy responder STK authentication from MITM state

The legacy responder path in smp_random() currently labels the stored STK as authenticated whenever pending_sec_level is BT_SECURITY_HIGH. That reflects what the local service requested, not what the pairing flow actually achieved.

For Just Works/Confirm legacy pairing, SMP_FLAG_MITM_AUTH stays clear and the resulting STK should remain unauthenticated even if the local side requested HIGH security. Use the established MITM state when storing the responder STK so the key metadata matches the pairing result.

This also keeps the legacy path aligned with the Secure Connections code, which already treats JUST_WORKS/JUST_CFM as unauthenticated.

CVSS v3
8.8
EG Score
8.8(medium)
EG Risk
44(Track)
EG Risk 44/100SSVC: 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
Severity88% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
20%
KEV
Not listed

Published

May 1, 2026

Last Modified

May 11, 2026

Advisory Details (8)

Auto-updated May 3, 2026
No patch confirmed yet.
generic

Bluetooth: SMP: derive legacy responder STK authentication from MITM state - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/b1c6a8e554a39b222c0879a288ea98e338fc4d77
generic

Bluetooth: SMP: derive legacy responder STK authentication from MITM state - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/9a6d0db176f082685e0b6149700c0baf3ce2aa8b
generic

Bluetooth: SMP: derive legacy responder STK authentication from MITM state - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/9a38659a3d06080715691bd3139f9c4b61f688e3
generic

Bluetooth: SMP: derive legacy responder STK authentication from MITM state - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/929db734d12db41ca5f95424db4612397f1bd4a7
generic

Bluetooth: SMP: derive legacy responder STK authentication from MITM state - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/667f44f1392df6482483756458c48670e579e9ff
generic

Bluetooth: SMP: derive legacy responder STK authentication from MITM state - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/20756fec2f0108cb88e815941f1ffff88dc286fe
generic

Bluetooth: SMP: derive legacy responder STK authentication from MITM state - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/0afc846bd80073ffcd2b8040f2b2fafaea3d9f72
generic

Bluetooth: SMP: derive legacy responder STK authentication from MITM state - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/061ee71ac6b03c9f8432fe49538c3682bfcf4cf3

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.

Data Freshness Timeline

(refreshed 12× in last 7d / 44× 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 145 total refreshes for this CVE.

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

Frequently asked(5)

What is CVE-2026-31773?
CVE-2026-31773 is a high vulnerability published on May 1, 2026. In the Linux kernel, the following vulnerability has been resolved: Bluetooth: SMP: derive legacy responder STK authentication from MITM state The legacy responder path in smp_random() currently labels the stored STK as authenticated whenever pendingseclevel is BTSECURITYHIGH. That reflects what…
When was CVE-2026-31773 disclosed?
CVE-2026-31773 was first published in the National Vulnerability Database on May 1, 2026, with the most recent update on May 11, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-31773 actively exploited?
CVE-2026-31773 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 79.6% of all scored CVEs.
What is the CVSS score of CVE-2026-31773?
CVE-2026-31773 has a CVSS v3 base score of 8.8 (NVD).
How do I remediate CVE-2026-31773?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-31773, 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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