CVE-2026-43491

MEDIUMNVD 5.55.5—
EchelonGraph scoreMEDIUM confidence

Score 5.5 from GitHub Security Advisory published 2026-05-19. 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:

net: qrtr: ns: Limit the maximum server registration per node

Current code does no bound checking on the number of servers added per node. A malicious client can flood NEW_SERVER messages and exhaust memory.

Fix this issue by limiting the maximum number of server registrations to 256 per node. If the NEW_SERVER message is received for an old port, then don't restrict it as it will get replaced. While at it, also rate limit the error messages in the failure path of qrtr_ns_worker().

Note that the limit of 256 is chosen based on the current platform requirements. If requirement changes in the future, this limit can be increased.

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

May 19, 2026

Last Modified

August 19, 2026

Advisory Details (5)

Auto-updated Jun 26, 2026
No patch confirmed yet.
generic

net: qrtr: ns: Limit the maximum server registration per node - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/e6f6cd501fb54060940a6eb3f4103eeb5e426ae7
generic

net: qrtr: ns: Limit the maximum server registration per node - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/d5ee2ff98322337951c56398e79d51815acbf955
generic

net: qrtr: ns: Limit the maximum server registration per node - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/868202aa2adae427060a42d5bd663b4d782ec02c
generic

net: qrtr: ns: Limit the maximum server registration per node - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/3efaad55cad1ded429e3a873bfece389058a526b
generic

net: qrtr: ns: Limit the maximum server registration per node - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/35fb4a0c077c5d1049c2628b769e0a1b1e65df0d

Vendor Advisories for CVE-2026-43491(2)

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

Patch Availability(21)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntulinux-tools-nvidia-lowlatency-64k-6.8 (6.8.0-1059.62.1) @ noble2026-08-23ubuntu
ubuntulinux-tools-azure-fde-7.0 (7.0.0-1009.9) @ resolute2026-08-23ubuntu
ubuntulinux-virtual-hwe-26.04-edge (7.0.0-27.27) @ resolute2026-08-23ubuntu
ubuntulinux-tools-oem-7.0 (7.0.0-1008.8) @ resolute2026-08-23ubuntu
ubuntulinux-tools-raspi-realtime-7.0 (7.0.0-1014.14) @ resolute2026-08-23ubuntu
ubuntulinux-tools-nvidia-hwe-24.04-edge (7.0.0-1013.13) @ resolute2026-08-23ubuntu
ubuntulinux-virtual-6.8 (6.8.0-136.136) @ noble2026-08-23ubuntu
ubuntulinux-virtual-hwe-24.04-edge (7.0.0-28.28~24.04.1) @ 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-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-raspi-realtime-6.8 (6.8.0-2050.52) @ noble2026-08-23ubuntu
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
ubuntulinux-tools-gcp-fips-6.8 (6.8.0-1064.72+fips1) @ noble2026-08-23ubuntu
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

(4 across 4 ecosystems)
Debian:11(1)
PackageVulnerable rangeFixed inDependents
linux5.10.103-1 ... 7.2~rc5-1~exp1 (496 versions)——
Debian:12(1)
PackageVulnerable rangeFixed inDependents
linux6.1.106-1 ... 7.2~rc5-1~exp1 (335 versions)——
Debian:13(1)
PackageVulnerable rangeFixed inDependents
linux6.12.38-1 ... 6.12.86-1~bpo12+1 (19 versions)6.12.86-1—
Debian:14(1)
PackageVulnerable rangeFixed inDependents
linux6.12.100-1 ... 7.0.4-1~bpo13+1 (131 versions)7.0.4-1—

Additional Vendor Advisories

(20)

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 5× in last 7d / 63× 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 185 total refreshes for this CVE.

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

Frequently asked(5)

What is CVE-2026-43491?
CVE-2026-43491 is a medium vulnerability published on May 19, 2026. In the Linux kernel, the following vulnerability has been resolved: net: qrtr: ns: Limit the maximum server registration per node Current code does no bound checking on the number of servers added per node. A malicious client can flood NEW_SERVER messages and exhaust memory. Fix this issue by…
When was CVE-2026-43491 disclosed?
CVE-2026-43491 was first published in the National Vulnerability Database on May 19, 2026, with the most recent update on August 19, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-43491 actively exploited?
CVE-2026-43491 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 95.6% of all scored CVEs.
What is the CVSS score of CVE-2026-43491?
CVE-2026-43491 has a CVSS v3 base score of 5.5 (NVD).
How do I remediate CVE-2026-43491?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-43491, 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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