CVE-2026-43109

MEDIUMNVD 5.55.5—
EchelonGraph scoreMEDIUM confidence

Score 5.5 from GitHub Security Advisory published 2026-05-06. NVD baseline CVSS 5.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
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:

x86: shadow stacks: proper error handling for mmap lock

김영민 reports that shstk_pop_sigframe() doesn't check for errors from mmap_read_lock_killable(), which is a silly oversight, and also shows that we haven't marked those functions with "__must_check", which would have immediately caught it.

So let's fix both issues.

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
2%
KEV
Not listed

Published

May 6, 2026

Last Modified

May 17, 2026

Advisory Details (5)

Auto-updated May 17, 2026
No patch confirmed yet.
generic

x86: shadow stacks: proper error handling for mmap lock - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/c79cf42321600e931933e11f94aba8b245d4cd66
generic

x86: shadow stacks: proper error handling for mmap lock - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/c64cebcc5c4f223dbcbe7dcdf74908fc092a0aa4
generic

x86: shadow stacks: proper error handling for mmap lock - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/52f657e34d7b21b47434d9d8b26fa7f6778b63a0
generic

x86: shadow stacks: proper error handling for mmap lock - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/262b6d38a81d51b135db81e1f30c13d30e38feee
generic

x86: shadow stacks: proper error handling for mmap lock - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/1a30468eff661937d978495644d2e5ebfeef5ce6

Vendor Advisories for CVE-2026-43109(2)

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

Patch Availability(15)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntulinux-tools-raspi-realtime-6.8 (6.8.0-2050.52) @ noble2026-08-23ubuntu
ubuntulinux-virtual-6.8 (6.8.0-136.136) @ noble2026-08-23ubuntu
ubuntulinux-tools-gcp-fips-6.8 (6.8.0-1064.72+fips1) @ noble2026-08-23ubuntu
ubuntulinux-tools-oracle-lts-24.04 (6.8.0-1058.61) @ noble2026-08-23ubuntu
ubuntulinux-tools-oracle-edge (6.8.0-1058.61~22.04.1) @ jammy2026-08-23ubuntu
ubuntulinux-tools-nvidia-lowlatency-64k-6.8 (6.8.0-1059.62.1) @ noble2026-08-23ubuntu
ubuntulinux-tools-aws-lts-24.04 (6.8.0-1061.64+1) @ noble2026-08-23ubuntu
ubuntulinux-tools-azure-lts-24.04 (6.8.0-1063.71) @ noble2026-08-23ubuntu
ubuntulinux-tools-azure-fde-lts-24.04 (6.8.0-1062.69) @ noble2026-08-23ubuntu
ubuntulinux-tools-azure-fips-6.8 (6.8.0-1063.71+fips2) @ noble2026-08-23ubuntu
ubuntulinux-tools-azure-fde-6.8 (6.8.0-1062.69~22.04.1) @ jammy2026-08-23ubuntu
ubuntulinux-tools-aws-fips-6.8 (6.8.0-1061.64+fips1) @ noble2026-08-23ubuntu
ubuntulinux-xilinx-zynqmp (6.8.0.1033.34) @ noble2026-08-23ubuntu
ubuntulinux-virtual-hwe-22.04-edge (6.8.0-136.136~22.04.1) @ jammy2026-08-23ubuntu
linuxKernel @ 6.6.140—osv

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 ... 6.12.88-1~bpo12+1 (21 versions)6.12.88-1—
Debian:14(1)
PackageVulnerable rangeFixed inDependents
linux6.12.100-1 ... 6.19~rc8-1~exp1 (126 versions)6.19.14-1—

All Vendor Advisories

(14)

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 4× in last 7d / 54× 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 170 total refreshes for this CVE.

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

Related CVEs(same product + same vendor)

Frequently asked(5)

What is CVE-2026-43109?
CVE-2026-43109 is a medium vulnerability published on May 6, 2026. In the Linux kernel, the following vulnerability has been resolved: x86: shadow stacks: proper error handling for mmap lock 김영민 reports that shstkpopsigframe() doesn't check for errors from mmapreadlock_killable(), which is a silly oversight, and also shows that we haven't marked those functions…
When was CVE-2026-43109 disclosed?
CVE-2026-43109 was first published in the National Vulnerability Database on May 6, 2026, with the most recent update on May 17, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-43109 actively exploited?
CVE-2026-43109 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 98.4% of all scored CVEs.
What is the CVSS score of CVE-2026-43109?
CVE-2026-43109 has a CVSS v3 base score of 5.5 (NVD).
How do I remediate CVE-2026-43109?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-43109, 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-2026-43109

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