CVE-2026-53251

MEDIUMNVD 5.55.5—
EchelonGraph scoreHIGH confidence

Score 5.5 from GitHub Security Advisory published 2026-06-25. 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:

Bluetooth: ISO: Fix not releasing hdev reference on iso_conn_big_sync

hci_get_route() returns a reference-counted hci_dev pointer via hci_dev_hold(). The function exits normally or with an error without ever releasing it.

CVSS v3
5.5
EG Score
5.5(high)
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
2.8%
KEV
Not listed

Published

June 25, 2026

Last Modified

July 8, 2026

Advisory Details (4)

Auto-updated Jul 8, 2026
No patch confirmed yet.
generic

Bluetooth: ISO: Fix not releasing hdev reference on iso_conn_big_sync - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/5cbf290b79351971f20c7a533247e8d58a3f970c
generic

Bluetooth: ISO: Fix not releasing hdev reference on iso_conn_big_sync - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/4bbec25f47b930101294fd310c627c3f53e9661f
generic

Bluetooth: ISO: Fix not releasing hdev reference on iso_conn_big_sync - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/33d677d2e3713d98012c3dbd4a9207f7d785b854
generic

Bluetooth: ISO: Fix not releasing hdev reference on iso_conn_big_sync - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/23e8eb16820b866528fb300dc67fe3f67f00ef62

Vendor Advisories for CVE-2026-53251(1)

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

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 9× in last 7d / 55× 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. 2026-07-23 14:18 UTCEPSS rescore
  2. 2026-07-23 03:19 UTCEG score recompute
  3. 2026-07-22 14:08 UTCEPSS rescore
  4. 2026-07-21 15:25 UTCEPSS rescore
  5. 2026-07-20 17:08 UTCEPSS rescore
  6. 2026-07-19 02:29 UTCEPSS rescore
  7. 2026-07-18 10:04 UTCEPSS rescore
  8. 2026-07-17 03:52 UTCGHSA enrichment
  9. 2026-07-16 17:03 UTCEPSS rescore
  10. 2026-07-16 02:29 UTCGHSA enrichment
  11. 2026-07-15 16:57 UTCEPSS rescore
  12. 2026-07-15 16:57 UTCEPSS rescore
  13. 2026-07-15 02:00 UTCEPSS rescore
  14. 2026-07-15 02:00 UTCEPSS rescore
  15. 2026-07-15 01:10 UTCGHSA enrichment
  16. 2026-07-13 23:50 UTCGHSA enrichment
  17. 2026-07-13 22:31 UTCEPSS rescore
  18. 2026-07-13 06:13 UTCEPSS rescore
  19. 2026-07-13 06:13 UTCEPSS rescore
  20. 2026-07-12 22:31 UTCGHSA enrichment
  21. 2026-07-12 05:46 UTCEPSS rescore
  22. 2026-07-11 21:11 UTCEG score recompute▲ 5.50
  23. 2026-07-11 21:11 UTCGHSA enrichment
  24. 2026-07-11 08:27 UTCEPSS rescore
  25. 2026-07-11 08:27 UTCEPSS rescore
Show 30 more
  1. 2026-07-09 19:10 UTCEPSS rescore
  2. 2026-07-09 19:10 UTCEPSS rescore
  3. 2026-07-08 16:51 UTCNVD updateCVSS v3 → 5.5 · severity → MEDIUM
  4. 2026-07-08 15:16 UTCEPSS rescore
  5. 2026-07-08 15:16 UTCEPSS rescore
  6. 2026-07-08 14:11 UTCGHSA enrichment
  7. 2026-07-07 13:46 UTCEPSS rescore
  8. 2026-07-07 13:46 UTCEPSS rescore
  9. 2026-07-06 16:27 UTCEPSS rescore
  10. 2026-07-06 16:27 UTCEPSS rescore
  11. 2026-07-06 02:23 UTCEPSS rescore
  12. 2026-07-06 02:23 UTCEPSS rescore
  13. 2026-07-05 07:07 UTCGHSA enrichment
  14. 2026-07-05 02:31 UTCEPSS rescore
  15. 2026-07-05 02:30 UTCEPSS rescore
  16. 2026-07-04 06:31 UTCEPSS rescore
  17. 2026-07-04 06:31 UTCEPSS rescore
  18. 2026-07-02 00:05 UTCGHSA enrichment
  19. 2026-07-01 15:07 UTCEPSS rescore
  20. 2026-06-30 23:22 UTCEPSS rescore
  21. 2026-06-29 14:06 UTCEPSS rescore
  22. 2026-06-29 14:06 UTCEPSS rescore
  23. 2026-06-28 17:05 UTCGHSA enrichment
  24. 2026-06-28 14:07 UTCEPSS rescore
  25. 2026-06-28 04:56 UTCEPSS rescore
  26. 2026-06-28 04:56 UTCEPSS rescore
  27. 2026-06-27 03:08 UTCEPSS rescore
  28. 2026-06-25 13:49 UTCEPSS rescore
  29. 2026-06-25 10:04 UTCEG score recompute
  30. 2026-06-25 10:04 UTCGHSA enrichment

Frequently asked(5)

What is CVE-2026-53251?
CVE-2026-53251 is a medium vulnerability published on June 25, 2026. In the Linux kernel, the following vulnerability has been resolved: Bluetooth: ISO: Fix not releasing hdev reference on isoconnbig_sync hcigetroute() returns a reference-counted hci_dev pointer via hcidevhold(). The function exits normally or with an error without ever releasing it.
When was CVE-2026-53251 disclosed?
CVE-2026-53251 was first published in the National Vulnerability Database on June 25, 2026, with the most recent update on July 8, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-53251 actively exploited?
CVE-2026-53251 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 2.8% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-53251?
CVE-2026-53251 has a CVSS v3 base score of 5.5 (NVD).
How do I remediate CVE-2026-53251?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-53251, 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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