CVE-2026-53243

MEDIUMNVD 5.55.5—
EchelonGraph scoreMEDIUM 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 — 4 sources updated this week
5.5EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 5.5Exploit: None knownExposed: 0

A fix is available — apply it.

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

rseq: Fix using an uninitialized stack variable in rseq_exit_user_update()

There is an bug in which an uninitialized stack variable is used in rseq_exit_user_update() as reported by syzbot:

BUG: KMSAN: kernel-infoleak in rseq_set_ids_get_csaddr include/linux/rseq_entry.h:502 [inline]

The local variable:

struct rseq_ids ids = { .cpu_id = task_cpu(t), .mm_cid = task_mm_cid(t), .node_id = cpu_to_node(ids.cpu_id), };

According to the C standard, the evaluation order of expressions in an initializer list is indeterminately sequenced. The compiler (Clang, in this KMSAN build) evaluates cpu_to_node(ids.cpu_id) *before* ids.cpu_id is initialized with task_cpu(t).

This is fixed by moving the assignment of ids.node_id outside the structure initialization.

CVSS v3
5.5
EG Score
5.5(medium)
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 PROB
0%
EPSS %ILE
4%
KEV
Not listed

Published

June 25, 2026

Last Modified

July 7, 2026

Advisory Details (2)

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

rseq: Fix using an uninitialized stack variable in rseq_exit_user_update() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/e12d20a63b61aaf9de4772effccf42cc9a003e58
generic

rseq: Fix using an uninitialized stack variable in rseq_exit_user_update() - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/6d99479799c69c3cb588fcda19c81d8f61d64ecd

Vendor Advisories for CVE-2026-53243(1)

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

Patch Availability(3)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntulinux-tools-nvidia-hwe-24.04-edge (7.0.0-1018.18~24.04.1) @ noble2026-09-18ubuntu
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

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

(1 across 1 ecosystem)
Debian:14(1)
PackageVulnerable rangeFixed inDependents
linux6.12.100-1 ... 7.0.9-1~bpo13+1 (145 versions)7.0.13-1—

Weakness Classification(1)

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

All Vendor Advisories

(3)

Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.

Data Freshness Timeline

(refreshed 10× in last 7d / 40× 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 159 total refreshes for this CVE.

  1. 2026-09-18 19:28 UTCEPSS rescore
  2. 2026-09-18 07:30 UTCEG score recompute
  3. 2026-09-18 07:30 UTCVendor advisory
  4. 2026-09-18 07:30 UTCGHSA enrichment
  5. 2026-09-16 14:08 UTCEPSS rescore
  6. 2026-09-16 05:15 UTCEPSS rescore
  7. 2026-09-14 01:23 UTCEG score recompute
  8. 2026-09-14 01:23 UTCVendor advisory
  9. 2026-09-14 01:23 UTCGHSA enrichment
  10. 2026-09-13 16:47 UTCEPSS rescore
  11. 2026-09-12 15:56 UTCEG score recompute
  12. 2026-09-12 15:56 UTCVendor advisory
  13. 2026-09-12 15:56 UTCGHSA enrichment
  14. 2026-09-11 14:53 UTCEPSS rescore
  15. 2026-09-10 09:35 UTCEPSS rescore
  16. 2026-09-08 22:01 UTCEPSS rescore
  17. 2026-09-07 16:01 UTCEPSS rescore
  18. 2026-09-06 13:47 UTCEPSS rescore
  19. 2026-09-04 05:06 UTCEPSS rescore
  20. 2026-09-02 14:12 UTCEPSS rescore
  21. 2026-09-01 13:54 UTCEPSS rescore
  22. 2026-09-01 04:40 UTCEPSS rescore
  23. 2026-08-30 19:37 UTCEG score recompute
  24. 2026-08-30 19:37 UTCGHSA enrichment
  25. 2026-08-30 19:17 UTCEPSS rescore
Show 75 more
  1. 2026-08-30 01:22 UTCEPSS rescore
  2. 2026-08-28 21:41 UTCEPSS rescore
  3. 2026-08-27 23:58 UTCEG score recompute
  4. 2026-08-27 23:58 UTCGHSA enrichment
  5. 2026-08-27 14:25 UTCEPSS rescore
  6. 2026-08-26 14:46 UTCEPSS rescore
  7. 2026-08-25 13:49 UTCEPSS rescore
  8. 2026-08-24 13:12 UTCEG score recompute
  9. 2026-08-24 13:12 UTCGHSA enrichment
  10. 2026-08-23 09:26 UTCEG score recompute
  11. 2026-08-23 09:26 UTCGHSA enrichment
  12. 2026-08-23 00:19 UTCEPSS rescore
  13. 2026-08-22 10:42 UTCGHSA enrichment
  14. 2026-08-21 05:52 UTCEG score recompute
  15. 2026-08-21 05:52 UTCGHSA enrichment
  16. 2026-08-20 22:55 UTCEPSS rescore
  17. 2026-08-20 07:07 UTCEG score recompute
  18. 2026-08-20 07:07 UTCGHSA enrichment
  19. 2026-08-19 17:04 UTCEPSS rescore
  20. 2026-08-19 01:31 UTCEG score recompute
  21. 2026-08-19 01:31 UTCGHSA enrichment
  22. 2026-08-18 13:48 UTCEPSS rescore
  23. 2026-08-17 13:47 UTCEPSS rescore
  24. 2026-08-17 02:46 UTCEG score recompute
  25. 2026-08-17 02:46 UTCGHSA enrichment
  26. 2026-08-16 14:56 UTCEPSS rescore
  27. 2026-08-16 04:01 UTCEG score recompute
  28. 2026-08-16 04:01 UTCGHSA enrichment
  29. 2026-08-16 02:14 UTCEPSS rescore
  30. 2026-08-15 05:16 UTCEG score recompute
  31. 2026-08-15 05:16 UTCGHSA enrichment
  32. 2026-08-15 01:30 UTCEPSS rescore
  33. 2026-08-14 06:31 UTCEG score recompute
  34. 2026-08-14 06:31 UTCGHSA enrichment
  35. 2026-08-13 22:00 UTCEPSS rescore
  36. 2026-08-13 07:46 UTCEG score recompute
  37. 2026-08-13 07:46 UTCGHSA enrichment
  38. 2026-08-12 13:51 UTCEPSS rescore
  39. 2026-08-12 08:24 UTCEG score recompute
  40. 2026-08-12 08:24 UTCGHSA enrichment
  41. 2026-08-11 09:39 UTCEG score recompute
  42. 2026-08-11 09:39 UTCGHSA enrichment
  43. 2026-08-11 00:00 UTCEPSS rescore
  44. 2026-08-10 10:55 UTCEG score recompute
  45. 2026-08-10 10:55 UTCGHSA enrichment
  46. 2026-08-09 13:46 UTCEPSS rescore
  47. 2026-08-09 12:10 UTCGHSA enrichment
  48. 2026-08-08 13:25 UTCEG score recompute
  49. 2026-08-08 13:25 UTCGHSA enrichment
  50. 2026-08-07 14:40 UTCGHSA enrichment
  51. 2026-08-06 15:56 UTCEG score recompute
  52. 2026-08-06 15:56 UTCGHSA enrichment
  53. 2026-08-06 13:47 UTCEPSS rescore
  54. 2026-08-05 17:10 UTCGHSA enrichment
  55. 2026-08-04 18:23 UTCEG score recompute
  56. 2026-08-04 18:23 UTCGHSA enrichment
  57. 2026-08-04 15:10 UTCEPSS rescore
  58. 2026-08-03 19:23 UTCEG score recompute
  59. 2026-08-03 19:23 UTCGHSA enrichment
  60. 2026-08-03 10:36 UTCEPSS rescore
  61. 2026-08-02 20:38 UTCEG score recompute
  62. 2026-08-02 20:38 UTCGHSA enrichment
  63. 2026-08-02 02:27 UTCEPSS rescore
  64. 2026-08-01 21:53 UTCEG score recompute
  65. 2026-08-01 21:53 UTCGHSA enrichment
  66. 2026-08-01 04:16 UTCEPSS rescore
  67. 2026-07-31 23:08 UTCGHSA enrichment
  68. 2026-07-30 23:59 UTCEG score recompute
  69. 2026-07-30 23:59 UTCGHSA enrichment
  70. 2026-07-30 16:28 UTCEPSS rescore
  71. 2026-07-30 01:14 UTCGHSA enrichment
  72. 2026-07-28 21:24 UTCEG score recompute
  73. 2026-07-28 21:24 UTCGHSA enrichment
  74. 2026-07-28 15:37 UTCEPSS rescore
  75. 2026-07-27 17:26 UTCEG score recompute

Frequently asked(5)

What is CVE-2026-53243?
CVE-2026-53243 is a medium vulnerability published on June 25, 2026. In the Linux kernel, the following vulnerability has been resolved: rseq: Fix using an uninitialized stack variable in rseqexituser_update() There is an bug in which an uninitialized stack variable is used in rseqexituser_update() as reported by syzbot: BUG: KMSAN: kernel-infoleak in…
When was CVE-2026-53243 disclosed?
CVE-2026-53243 was first published in the National Vulnerability Database on June 25, 2026, with the most recent update on July 7, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-53243 actively exploited?
CVE-2026-53243 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 96.0% of all scored CVEs.
What is the CVSS score of CVE-2026-53243?
CVE-2026-53243 has a CVSS v3 base score of 5.5 (NVD).
How do I remediate CVE-2026-53243?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-53243, 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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