CVE-2026-63889

HIGHPre-NVD 8.18.1
EchelonGraph scoreMEDIUM confidence

Score 8.1 from GitHub Security Advisory (severity: HIGH) published 2026-07-19. the CNA's CVSS baseline 8.1; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cna:linux, epss, ghsa
Trending — 4 sources updated this week
8.1EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 8.1Exploit: None knownExposed: 0

A fix is available — apply it.

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

scsi: scsi_transport_fc: Widen FPIN pname walker counter to u32

An adjacent Fibre Channel fabric actor that can deliver an FPIN ELS frame to an lpfc or qla2xxx Linux initiator can trigger a non-return in the generic FC transport. This is not a local userspace or IP network path; the attacker must be able to inject fabric traffic, for example as a compromised switch or fabric controller, or as a same-zone N_Port on a fabric that permits source spoofing.

The Link-Integrity and Peer-Congestion FPIN walkers used a u8 loop counter against the 32-bit on-wire pname_count field, and did not bound pname_count by the descriptor body already validated by the TLV walker. A pname_count of 256 therefore wraps the counter and keeps the loop condition true indefinitely.

Factor the shared pname_list[] walk into one helper, widen the counter to u32, and clamp pname_count against the entries that fit in the descriptor body before iterating.

CVSS v3
8.1
EG Score
8.1(medium)
EG Risk
41(Track)
EG Risk 41/100SSVC: 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
Severity81% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
29%
KEV
Not listed

Published

July 19, 2026

Last Modified

August 5, 2026

Advisory Details (7)

Auto-updated Jul 21, 2026
No patch confirmed yet.
generic

scsi: scsi_transport_fc: Widen FPIN pname walker counter to u32 - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/ee57b89e5da9fffbe0d26647e4ff0750dacb9943
generic

scsi: scsi_transport_fc: Widen FPIN pname walker counter to u32 - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/bdff76dff6ec23d6fe35812fa33e5c4ce2cdb770
generic

scsi: scsi_transport_fc: Widen FPIN pname walker counter to u32 - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/a9a39233ec1fc9f97ea1340a4d09bb7ec2be5153
generic

scsi: scsi_transport_fc: Widen FPIN pname walker counter to u32 - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/35461d23744175a78b6280293892cca357c22793
generic

scsi: scsi_transport_fc: Widen FPIN pname walker counter to u32 - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/29f126f09e34a425b376b3646c89aa7cc18b142c
generic

scsi: scsi_transport_fc: Widen FPIN pname walker counter to u32 - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/163bd704d7515c3df6c2e03bcba93d1db79edbff
generic

scsi: scsi_transport_fc: Widen FPIN pname walker counter to u32 - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/07776b7779c9426982c1ad74aad91bd531593790

Vendor Advisories for CVE-2026-63889(1)

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

Patch Availability(5)

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

(3 across 3 ecosystems)
Debian:12(1)
PackageVulnerable rangeFixed inDependents
linux6.1.106-1 ... 6.1.99-1 (53 versions)6.1.176-1
Debian:13(1)
PackageVulnerable rangeFixed inDependents
linux6.12.38-1 ... 6.12.94-1~bpo12+1 (27 versions)6.12.94-1
Debian:14(1)
PackageVulnerable rangeFixed inDependents
linux6.12.100-1 ... 7.0.9-1~bpo13+1 (138 versions)7.0.12-1

All Vendor Advisories

(5)

Data Freshness Timeline

(refreshed 33× in last 7d / 176× 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 225 total refreshes for this CVE.

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

Frequently asked(5)

What is CVE-2026-63889?
CVE-2026-63889 is a high vulnerability published on July 19, 2026. In the Linux kernel, the following vulnerability has been resolved: scsi: scsitransportfc: Widen FPIN pname walker counter to u32 An adjacent Fibre Channel fabric actor that can deliver an FPIN ELS frame to an lpfc or qla2xxx Linux initiator can trigger a non-return in the generic FC transport.…
When was CVE-2026-63889 disclosed?
CVE-2026-63889 was first published in the National Vulnerability Database on July 19, 2026, with the most recent update on August 5, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-63889 actively exploited?
CVE-2026-63889 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 71.4% of all scored CVEs.
What is the CVSS score of CVE-2026-63889?
CVE-2026-63889 has a CVSS v4.0 base score of 8.1 (CNA self-assessment; NVD's own analysis pending).
How do I remediate CVE-2026-63889?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-63889, 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

See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-63889

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