CVE-2026-63893

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:

thunderbolt: property: Reject u32 wrap in tb_property_entry_valid()

entry->value is u32 and entry->length is u16; the sum is performed in u32 and wraps. A malicious XDomain peer can pick value = 0xffffff00, length = 0x100 so the sum 0x100000000 wraps to 0 and passes the > block_len check. tb_property_parse() then passes entry->value to parse_dwdata() as a dword offset into the property block, reading attacker-directed memory far past the allocation.

For TEXT-typed entries with the "deviceid" or "vendorid" keys this lands in xd->device_name / xd->vendor_name and is readable back via the per-XDomain device_name / vendor_name sysfs attributes; the leak is NUL-bounded (kstrdup() stops at the first zero byte) and untargeted (the attacker picks a delta, not an absolute address). DATA-typed entries are parsed into property->value.data but not generically surfaced to userspace.

Use check_add_overflow() so a wrapped sum is rejected.

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
32%
KEV
Not listed

Published

July 19, 2026

Last Modified

August 5, 2026

Advisory Details (8)

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

thunderbolt: property: Reject u32 wrap in tb_property_entry_valid() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/e8a0b0a93a6ef958e70b1dd4930beb6dc0026b36
generic

thunderbolt: property: Reject u32 wrap in tb_property_entry_valid() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/a47784aee77f33f786dc5d7375db821bdae68792
generic

thunderbolt: property: Reject u32 wrap in tb_property_entry_valid() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/9fee50c4e1e42f6d3cbe30df584f9f648f626071
generic

thunderbolt: property: Reject u32 wrap in tb_property_entry_valid() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/8d4a758b407ab3de3be86d1ceadfa35d717d30c7
generic

thunderbolt: property: Reject u32 wrap in tb_property_entry_valid() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/6a63623621639acbb39bc2d9fb09559681716695
generic

thunderbolt: property: Reject u32 wrap in tb_property_entry_valid() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/5c06a3043ad944f087bb2ae0aae28d820bb9f460
generic

thunderbolt: property: Reject u32 wrap in tb_property_entry_valid() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/31b98e503ecca8077e5247253dd5425ab84bc96d
generic

thunderbolt: property: Reject u32 wrap in tb_property_entry_valid() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/01deda0152066c6c955f0619114ea6afa070aaec

Vendor Advisories for CVE-2026-63893(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

(4 across 4 ecosystems)
Debian:11(1)
PackageVulnerable rangeFixed inDependents
linux5.10.103-1 ... 5.10.92-2 (54 versions)5.10.259-1
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 227 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 22:48 UTCEG score recompute
  7. 2026-08-27 22:48 UTCVendor advisory
  8. 2026-08-27 22:48 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 07:55 UTCVendor advisory
  17. 2026-08-26 07:55 UTCGHSA enrichment
  18. 2026-08-25 20:57 UTCEG score recompute
  19. 2026-08-25 20:57 UTCVendor advisory
  20. 2026-08-25 20:57 UTCGHSA enrichment
  21. 2026-08-25 13:49 UTCEPSS rescore
  22. 2026-08-25 10:04 UTCVendor advisory
  23. 2026-08-25 10:04 UTCGHSA enrichment
  24. 2026-08-24 23:10 UTCEG score recompute
  25. 2026-08-24 23:10 UTCVendor advisory
Show 75 more
  1. 2026-08-24 23:10 UTCGHSA enrichment
  2. 2026-08-24 12:17 UTCEG score recompute
  3. 2026-08-24 12:17 UTCVendor advisory
  4. 2026-08-24 12:17 UTCGHSA enrichment
  5. 2026-08-24 01:24 UTCVendor advisory
  6. 2026-08-24 01:24 UTCGHSA enrichment
  7. 2026-08-23 14:29 UTCVendor advisory
  8. 2026-08-23 14:29 UTCGHSA enrichment
  9. 2026-08-23 03:36 UTCEG score recompute
  10. 2026-08-23 03:36 UTCVendor advisory
  11. 2026-08-23 03:36 UTCGHSA enrichment
  12. 2026-08-23 00:19 UTCEPSS rescore
  13. 2026-08-22 16:42 UTCVendor advisory
  14. 2026-08-22 16:42 UTCGHSA enrichment
  15. 2026-08-22 05:38 UTCEG score recompute
  16. 2026-08-22 05:38 UTCVendor advisory
  17. 2026-08-22 05:38 UTCGHSA enrichment
  18. 2026-08-21 23:49 UTCEPSS rescore
  19. 2026-08-21 18:45 UTCVendor advisory
  20. 2026-08-21 18:45 UTCGHSA enrichment
  21. 2026-08-21 07:51 UTCEG score recompute
  22. 2026-08-21 07:51 UTCVendor advisory
  23. 2026-08-21 07:51 UTCGHSA enrichment
  24. 2026-08-20 22:55 UTCEPSS rescore
  25. 2026-08-20 20:58 UTCVendor advisory
  26. 2026-08-20 20:58 UTCGHSA enrichment
  27. 2026-08-20 10:05 UTCVendor advisory
  28. 2026-08-20 10:04 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 08:49 UTCVendor advisory
  46. 2026-08-17 08:49 UTCGHSA enrichment
  47. 2026-08-16 21:56 UTCEG score recompute
  48. 2026-08-16 21:56 UTCVendor advisory
  49. 2026-08-16 21:56 UTCGHSA enrichment
  50. 2026-08-16 14:56 UTCEPSS rescore
  51. 2026-08-16 11:03 UTCEG score recompute
  52. 2026-08-16 11:03 UTCVendor advisory
  53. 2026-08-16 11:03 UTCGHSA enrichment
  54. 2026-08-16 00:10 UTCVendor advisory
  55. 2026-08-16 00:10 UTCGHSA enrichment
  56. 2026-08-15 13:17 UTCVendor advisory
  57. 2026-08-15 13:17 UTCGHSA enrichment
  58. 2026-08-15 02:23 UTCEG score recompute
  59. 2026-08-15 02:23 UTCVendor advisory
  60. 2026-08-15 02:23 UTCGHSA enrichment
  61. 2026-08-15 01:30 UTCEPSS rescore
  62. 2026-08-14 15:30 UTCVendor advisory
  63. 2026-08-14 15:30 UTCGHSA enrichment
  64. 2026-08-14 04:37 UTCEG score recompute
  65. 2026-08-14 04:37 UTCVendor advisory
  66. 2026-08-14 04:37 UTCGHSA enrichment
  67. 2026-08-13 22:00 UTCEPSS rescore
  68. 2026-08-13 17:44 UTCVendor advisory
  69. 2026-08-13 17:44 UTCGHSA enrichment
  70. 2026-08-13 06:35 UTCVendor advisory
  71. 2026-08-13 06:35 UTCGHSA enrichment
  72. 2026-08-12 19:42 UTCEG score recompute
  73. 2026-08-12 19:42 UTCVendor advisory
  74. 2026-08-12 19:42 UTCGHSA enrichment
  75. 2026-08-12 13:51 UTCEPSS rescore

Frequently asked(5)

What is CVE-2026-63893?
CVE-2026-63893 is a high vulnerability published on July 19, 2026. In the Linux kernel, the following vulnerability has been resolved: thunderbolt: property: Reject u32 wrap in tbpropertyentry_valid() entry->value is u32 and entry->length is u16; the sum is performed in u32 and wraps. A malicious XDomain peer can pick value = 0xffffff00, length = 0x100 so the sum…
When was CVE-2026-63893 disclosed?
CVE-2026-63893 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-2026-63893 actively exploited?
CVE-2026-63893 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 68.5% of all scored CVEs.
What is the CVSS score of CVE-2026-63893?
CVE-2026-63893 has a CVSS v4.0 base score of 8.1 (CNA self-assessment; NVD's own analysis pending).
How do I remediate CVE-2026-63893?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-63893, 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-2026-63893

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