CVE-2026-90256

HIGHPre-NVD 8.88.8—
EchelonGraph scoreHIGH confidence

Score 8.8 from GitHub Security Advisory (severity: HIGH) published 2026-09-17. A secondary CVSS source baseline 8.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 3 sources updated this week
8.8EG
EchelonGraph verdictPlan mitigationSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0.3%CVSS: 8.8Exploit: None knownExposed services: Not assessed

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

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

Bluetooth: L2CAP: use proto_lock for l2cap_data to fix l2cap_disconn_ind

hci_conn::l2cap_data is accessed without locks in l2cap_disconn_ind via hci_conn_timeout (disc_work) -> hci_proto_disconn_ind -> l2cap_disconn_ind. This is UAF if the l2cap_conn is deleted concurrently.

disc_work is disabled sync in hci_conn_del(), so we cannot take hci_dev_lock in disc_work.

Fix by using proto_lock to guard l2cap_data, in addition to hdev->lock which is held in other access paths.

CVSS v3
8.8
EG Score
8.8HIGHhigh confidence
EG Risk
44
EG Risk 44/100CISA SSVC

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%
CISA SSVC: Track at low or medium mission impact; Track or Attend at high (mission-essential systems).
Action: No fix is confirmed yet. Restrict network exposure of the affected system or apply the vendor's mitigation within your standard update timelines at low or medium mission impact and sooner than that at high, and watch the vendor's advisory for the fix.
EPSS PROB
0.3%
EPSS %ILE
25th
KEV
Not listed

CISA SSVCTrack at low or medium mission impact; Track or Attend at high (mission-essential systems).

No fix is confirmed yet. Restrict network exposure of the affected system or apply the vendor's mitigation within your standard update timelines at low or medium mission impact and sooner than that at high, and watch the vendor's advisory for the fix.

Exploitation none (no KEV listing, exploit record or EPSS ≥ 50%) · Automatable unknown (not published for this CVE) · Technical impact partial (CVSS below 9.0). Mission impact is CISA's Mission & Well-being decision point, and only you can judge it: high means the affected system is essential to your organisation's mission, or its compromise could cause irreversible harm to people. CISA's decision table

Published

September 17, 2026

Last Modified

September 18, 2026

Advisory Details (2)

Auto-updated Sep 18, 2026
No patch confirmed yet.
generic

Bluetooth: L2CAP: use proto_lock for l2cap_data to fix l2cap_disconn_ind - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/2b66c83ff1751d6bd3201b3017206262ab46dc05
generic

Bluetooth: L2CAP: use proto_lock for l2cap_data to fix l2cap_disconn_ind - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/b495a3a9b33bc4e4613e685bf5c96c136caa22d8

Vendor Advisories for CVE-2026-90256(1)

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

Affected Packages

(2 across 2 ecosystems)
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
linux6.12.100-1 ... 7.2~rc7-1~exp1 (181 versions)
  • every version on: no fix on record
—
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
linux6.12.100-1 ... 7.2~rc7-1~exp1 (178 versions)
  • every version up to 7.2.6-1: fixed in 7.2.6-1
—

Data Freshness Timeline

(refreshed 26× in last 7d / 69× 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. 2026-10-05 04:27 UTCEG score recompute
  2. 2026-10-05 04:27 UTCGHSA enrichment
  3. 2026-10-04 23:22 UTCEPSS rescore
  4. 2026-10-04 15:20 UTCGHSA enrichment
  5. 2026-10-04 02:11 UTCEG score recompute
  6. 2026-10-04 02:11 UTCGHSA enrichment
  7. 2026-10-03 13:05 UTCGHSA enrichment
  8. 2026-10-02 23:58 UTCEG score recompute
  9. 2026-10-02 23:58 UTCGHSA enrichment
  10. 2026-10-02 10:51 UTCGHSA enrichment
  11. 2026-10-01 21:33 UTCEG score recompute
  12. 2026-10-01 21:33 UTCGHSA enrichment
  13. 2026-10-01 19:51 UTCEPSS rescore
  14. 2026-10-01 08:26 UTCGHSA enrichment
  15. 2026-09-30 19:19 UTCEG score recompute
  16. 2026-09-30 19:19 UTCGHSA enrichment
  17. 2026-09-30 15:04 UTCEPSS rescore
  18. 2026-09-30 06:13 UTCGHSA enrichment
  19. 2026-09-29 17:07 UTCEG score recompute
  20. 2026-09-29 17:06 UTCGHSA enrichment
  21. 2026-09-29 03:59 UTCEG score recompute
  22. 2026-09-29 03:59 UTCGHSA enrichment
  23. 2026-09-28 14:52 UTCEG score recompute
  24. 2026-09-28 14:52 UTCGHSA enrichment
  25. 2026-09-28 13:52 UTCEPSS rescore
Show 44 more
  1. 2026-09-28 13:52 UTCEPSS rescore
  2. 2026-09-28 01:45 UTCEG score recompute
  3. 2026-09-28 01:45 UTCGHSA enrichment
  4. 2026-09-27 13:49 UTCEPSS rescore
  5. 2026-09-27 12:36 UTCGHSA enrichment
  6. 2026-09-26 23:30 UTCEG score recompute
  7. 2026-09-26 23:29 UTCGHSA enrichment
  8. 2026-09-26 15:59 UTCEPSS rescore
  9. 2026-09-26 10:09 UTCEG score recompute
  10. 2026-09-26 10:09 UTCGHSA enrichment
  11. 2026-09-25 21:02 UTCGHSA enrichment
  12. 2026-09-25 07:55 UTCGHSA enrichment
  13. 2026-09-24 18:48 UTCEG score recompute
  14. 2026-09-24 18:48 UTCGHSA enrichment
  15. 2026-09-24 14:04 UTCEPSS rescore
  16. 2026-09-24 05:41 UTCEG score recompute
  17. 2026-09-24 05:41 UTCGHSA enrichment
  18. 2026-09-23 17:54 UTCEPSS rescore
  19. 2026-09-23 16:34 UTCGHSA enrichment
  20. 2026-09-23 03:28 UTCEG score recompute
  21. 2026-09-23 03:28 UTCGHSA enrichment
  22. 2026-09-22 16:01 UTCEPSS rescore
  23. 2026-09-22 14:21 UTCGHSA enrichment
  24. 2026-09-22 01:12 UTCEG score recompute
  25. 2026-09-22 01:12 UTCGHSA enrichment
  26. 2026-09-21 21:09 UTCEPSS rescore
  27. 2026-09-21 12:06 UTCGHSA enrichment
  28. 2026-09-20 22:59 UTCEG score recompute
  29. 2026-09-20 22:58 UTCGHSA enrichment
  30. 2026-09-20 20:16 UTCEPSS rescore
  31. 2026-09-20 09:51 UTCGHSA enrichment
  32. 2026-09-19 20:44 UTCEG score recompute
  33. 2026-09-19 20:44 UTCGHSA enrichment
  34. 2026-09-19 07:37 UTCEG score recompute
  35. 2026-09-19 07:37 UTCGHSA enrichment
  36. 2026-09-18 19:28 UTCEPSS rescore
  37. 2026-09-18 18:30 UTCEG score recompute
  38. 2026-09-18 18:30 UTCGHSA enrichment
  39. 2026-09-18 18:03 UTCEG score recompute▲ 8.80
  40. 2026-09-18 18:03 UTCGHSA enrichment
  41. 2026-09-18 17:59 UTCMITRE cvelistV5CVSS v3 → 8.8 · severity → HIGH
  42. 2026-09-17 17:24 UTCNVD update
  43. 2026-09-17 16:36 UTCEG score recompute
  44. 2026-09-17 16:19 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-90256?
CVE-2026-90256 is a high vulnerability published on September 17, 2026. In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: use protolock for l2capdata to fix l2capdisconnind hciconn::l2capdata is accessed without locks in l2capdisconnind via hciconntimeout (discwork) -> hciprotodisconnind -> l2capdisconnind. This is UAF if the…
When was CVE-2026-90256 disclosed?
CVE-2026-90256 was first published on September 17, 2026, with the most recent update on September 18, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-90256 actively exploited?
CVE-2026-90256 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.3% probability of exploitation in the next 30 days (25th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-90256?
CVE-2026-90256 has a CVSS base score of 8.8 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-90256?
No fix for CVE-2026-90256 is confirmed yet. Until one is published, restrict network exposure of the affected system or apply the vendor's mitigation — for example, keep it off the internet or limit it to trusted networks — and watch the vendor's advisory for the fix. The vendor advisories EchelonGraph has for CVE-2026-90256 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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