CVE-2026-63802

HIGHPre-NVD 7.87.8—
EchelonGraph scoreMEDIUM confidence

Score 7.8 from GitHub Security Advisory (severity: HIGH) published 2026-07-19. a secondary CVSS source baseline 7.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — Patch released this week
7.8EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 7.8Exploit: None knownExposed: 0

A fix is available — apply it.

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

blk-cgroup: fix UAF in __blkcg_rstat_flush()

When multiple blkgs in the same blkcg are released concurrently, a use-after-free can occur. The race happens when one blkg's __blkcg_rstat_flush() removes another blkg's iostat entries via llist_del_all(). The second blkg sees an empty list and proceeds to free itself while the first is still iterating over its entries.

Move the flush from __blkg_release() (RCU callback) to blkg_release() (before call_rcu). This ensures the RCU grace period waits for any concurrent flush's rcu_read_lock() section to complete before freeing.

CVSS v3
7.8
EG Score
7.8(medium)
EG Risk
40(Track)
EG Risk 40/100SSVC: 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
Severity78% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
3%
KEV
Not listed

Published

July 19, 2026

Last Modified

August 17, 2026

Advisory Details (5)

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

blk-cgroup: fix UAF in __blkcg_rstat_flush() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/bbebd9425cad3573d1527441753899b926525a0f
generic

blk-cgroup: fix UAF in __blkcg_rstat_flush() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/afebe44facc48a61761e885bbb7f0380d4a603ec
generic

blk-cgroup: fix UAF in __blkcg_rstat_flush() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/96e545410c4f74c89d496c1d5d9ef8d08f14368b
generic

blk-cgroup: fix UAF in __blkcg_rstat_flush() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/5e5b7f2ef854936e95dceb6a2fdfefcb7152d2c6
generic

blk-cgroup: fix UAF in __blkcg_rstat_flush() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/0ab5ee5a1badb58cbb2242617cb01a4972b1f2a2

Vendor Advisories for CVE-2026-63802(3)

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

Patch Availability(6)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntulinux-virtual-hwe-26.04-edge (7.0.0-31.31) @ resolute2026-09-18ubuntu
ubuntulinux-tools-oem-7.0 (7.0.0-1013.13) @ resolute2026-09-18ubuntu
ubuntulinux-tools-gcp-edge (7.0.0-1011.11~24.04.1) @ noble2026-09-18ubuntu
ubuntulinux-tools-nvidia-hwe-24.04-edge (7.0.0-1018.18~24.04.1) @ noble2026-09-18ubuntu
redhatkernel-rt-0:4.18.0-553.163.1.rt7.504.el8_102026-09-15redhat
redhatkernel-0:4.18.0-553.163.1.el8_102026-09-15redhat

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

(2 across 2 ecosystems)
Debian:13(1)
PackageVulnerable rangeFixed inDependents
linux6.12.38-1 ... 6.12.95-1~bpo12+1 (29 versions)6.12.95-1—
Debian:14(1)
PackageVulnerable rangeFixed inDependents
linux6.12.100-1 ... 7.1~rc7-1~exp1 (156 versions)7.1.3-1—

Weakness Classification(1)

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

Additional Vendor Advisories

(5)

Vendors that published advisories for this CVE beyond the curated set above. Broader coverage but minimal per-row detail — click through for the original advisory.

Data Freshness Timeline

(refreshed 19× in last 7d / 93× 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 220 total refreshes for this CVE.

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

Frequently asked(5)

What is CVE-2026-63802?
CVE-2026-63802 is a high vulnerability published on July 19, 2026. In the Linux kernel, the following vulnerability has been resolved: blk-cgroup: fix UAF in blkcgrstatflush() When multiple blkgs in the same blkcg are released concurrently, a use-after-free can occur. The race happens when one blkg's blkcgrstatflush() removes another blkg's iostat entries via…
When was CVE-2026-63802 disclosed?
CVE-2026-63802 was first published in the National Vulnerability Database on July 19, 2026, with the most recent update on August 17, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-63802 actively exploited?
CVE-2026-63802 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 96.8% of all scored CVEs.
What is the CVSS score of CVE-2026-63802?
CVE-2026-63802 has a CVSS v3 base score of 7.8 (NVD).
How do I remediate CVE-2026-63802?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-63802, 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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