CVE-2026-65423

HIGHPre-NVD 8.88.8—
EchelonGraph scoreMEDIUM confidence

Score 8.8 from GitHub Security Advisory (severity: HIGH) published 2026-07-31. A secondary CVSS source baseline 8.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 3 sources updated this week
8.8EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0.8%CVSS: 8.8Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

An integer overflow in the UA_Variant arrayDimensions product computation in open62541 may allow a remote attacker to trigger an out-of-bounds write.

CVSS v3
8.8
EG Score
8.8HIGHmedium confidence
EG Risk
40
EG Risk 40/100CISA SSVC

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
Severity88% × 45%
Exploitation1% × 40%
Automatability0% × 15%
CISA SSVC: Track at low or medium mission impact; Track* at high (mission-essential systems).
Action: A fix is available. Apply it within your standard update timelines.
EPSS PROB
0.8%
EPSS %ILE
55th
KEV
Not listed

CISA SSVCTrack at low or medium mission impact; Track* at high (mission-essential systems).

A fix is available. Apply it within your standard update timelines.

Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). Mission impact is CISA's Mission & Well-being decision point, and only you can judge it: high means the affected system is essential to your organisation's mission, or its compromise could cause irreversible harm to people. CISA's decision table

Published

July 30, 2026

Last Modified

September 3, 2026

Advisory Details (7)

Auto-updated Jul 30, 2026
⚠️ Active exploitation confirmed. Patch available. Sources: github_pr, cisa.
generic

CSAF/csaf_files/OT/white/2026/icsa-26-211-08.json at develop · cisagov/CSAF · GitHub

https://github.com/cisagov/CSAF/blob/develop/csaf_files/OT/white/2026/icsa-26-211-08.json
cisa Patch Available🔴 Active Exploitation

o6 Automation open62541 | CISA

o6 Automation open62541 | CISA. Listed in CISA Known Exploited Vulnerabilities catalog.

https://www.cisa.gov/news-events/ics-advisories/icsa-26-211-08
github_pr Patch Available

fix(server): migrate samplingMonitoredItems in TransferSubscriptions

Patch available: open62541/open62541 v1.3.19 (PR #8238 merged 2026-07-23)

https://github.com/open62541/open62541/pull/8238/commits/afab4107bfd161da9ce8bb30ed77f3968c9c97df
github_pr Patch Available

fix(pubsub): check message length before signature size subtraction

Patch available: open62541/open62541 v1.5.6 (PR #8237 merged 2026-07-24)

https://github.com/open62541/open62541/pull/8237/commits/1b71d9c5d9c4d02d4729b8903a52e9f530bf804e
github_pr Patch Available

fix(pubsub): check message length before signature size subtraction

Patch available: open62541/open62541 v1.3.19 (PR #8236 merged 2026-07-23)

https://github.com/open62541/open62541/pull/8236/commits/06b99fef667c8ec5bdf0605b4f00c84fcc1d3a60
github_pr Patch Available

fix(core): reject overflowing arrayDimensions product in Variant en/d…

Patch available: open62541/open62541 v1.3.19 (PR #8235 merged 2026-07-23)

https://github.com/open62541/open62541/pull/8235/commits/b666d35769ce63998442e4d0810a3fb10b50179f
generic

Contact | o6 Automation Website

https://www.o6-automation.com/contact

Vendor Advisories for CVE-2026-65423(1)

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

Affected Packages

(2 across 2 ecosystems)
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
open625411.4.11.1-1, 1.4.18-1
  • every version on: no fix on record
—
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
open625411.4.11.1-1, 1.4.18-1
  • every version on: no fix on record
—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 16× in last 7d / 78× 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 209 total refreshes for this CVE.

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

Related CVEs(same product + same CWE)

Frequently asked(5)

What is CVE-2026-65423?
CVE-2026-65423 is a high vulnerability published on July 30, 2026. An integer overflow in the UA_Variant arrayDimensions product computation in open62541 may allow a remote attacker to trigger an out-of-bounds write.
When was CVE-2026-65423 disclosed?
CVE-2026-65423 was first published on July 30, 2026, with the most recent update on September 3, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-65423 actively exploited?
CVE-2026-65423 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.8% probability of exploitation in the next 30 days (55th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-65423?
CVE-2026-65423 has a CVSS base score of 8.8 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-65423?
A fix for CVE-2026-65423 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-65423 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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