CVE-2026-11946

HIGHPre-NVD 7.57.5—
EchelonGraph scoreHIGH confidence

Score 7.5 from GitHub Security Advisory (severity: HIGH) published 2026-07-02. a secondary CVSS source baseline 7.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 3 sources updated this week
7.5
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 0%CVSS: 7.5Exploit: NoneExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

An unauthenticated remote attacker can exhaust server memory via the GetEndpoints Discovery Service in open62541. The endpointUrl field of GetEndpointsRequest is not validated for length. An attacker can declare an arbitrarily large string (up to ~4.09 GB via the UInt32 length field) delivered across intermediate chunks without ever sending the final chunk. The server buffers all chunks in RAM indefinitely until the SecureChannel times out. The attack is pre-session and bypasses all encryption configurations.

The issue affects open62541: from 1.4.0 through 1.4.16, from 1.5.0 through 1.5.4, master.

CVSS v3
7.5
EG Score
7.5(high)
EPSS
30.6%
KEV
Not listed

Published

July 2, 2026

Last Modified

July 2, 2026

Advisory Details (3)

Auto-updated Jul 3, 2026
Patch available. Sources: github_pr.
github_pr Patch Available

fix(server): Enforce default message and chunk size limits to prevent DoS

Patch available: open62541/open62541 v1.4.17 (PR #8142 merged 2026-06-23)

https://github.com/open62541/open62541/pull/8142/changes/d253818d6c5e870e1db0e360b18138c8bdc809ae
github_pr Patch Available

fix(server): Enforce default message and chunk size limits to prevent DoS

Patch available: open62541/open62541 v1.4.17 (PR #8142 merged 2026-06-23)

https://github.com/open62541/open62541/pull/8142
generic

GitHub - open62541/open62541: Open source implementation of OPC UA (OPC Unified Architecture) aka IEC 62541 licensed under Mozilla Public License v2.0 · GitHub

https://github.com/open62541/open62541

Vendor Advisories for CVE-2026-11946(1)

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

Weakness Classification(2)

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

Data Freshness Timeline

(refreshed 23× in last 7d / 23× 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.

  1. 2026-07-06 22:43 UTCEG score recompute
  2. 2026-07-06 22:43 UTCGHSA enrichment
  3. 2026-07-06 16:27 UTCEPSS rescore
  4. 2026-07-06 10:57 UTCEG score recompute
  5. 2026-07-06 10:57 UTCGHSA enrichment
  6. 2026-07-06 02:23 UTCEPSS rescore
  7. 2026-07-05 23:09 UTCEG score recompute
  8. 2026-07-05 23:09 UTCGHSA enrichment
  9. 2026-07-05 11:18 UTCEG score recompute
  10. 2026-07-05 11:18 UTCGHSA enrichment
  11. 2026-07-04 23:31 UTCEG score recompute
  12. 2026-07-04 23:31 UTCGHSA enrichment
  13. 2026-07-04 11:45 UTCEG score recompute
  14. 2026-07-04 11:44 UTCGHSA enrichment
  15. 2026-07-04 06:31 UTCEPSS rescore
  16. 2026-07-03 23:56 UTCEG score recompute
  17. 2026-07-03 23:56 UTCGHSA enrichment
  18. 2026-07-03 12:09 UTCEG score recompute
  19. 2026-07-03 12:09 UTCGHSA enrichment
  20. 2026-07-03 00:22 UTCEG score recompute
  21. 2026-07-03 00:22 UTCGHSA enrichment
  22. 2026-07-02 12:36 UTCEG score recompute
  23. 2026-07-02 12:36 UTCGHSA enrichment

Frequently asked(5)

What is CVE-2026-11946?
CVE-2026-11946 is a high vulnerability published on July 2, 2026. An unauthenticated remote attacker can exhaust server memory via the GetEndpoints Discovery Service in open62541. The endpointUrl field of GetEndpointsRequest is not validated for length. An attacker can declare an arbitrarily large string (up to ~4.09 GB via the UInt32 length field) delivered…
When was CVE-2026-11946 disclosed?
CVE-2026-11946 was first published in the National Vulnerability Database on July 2, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-11946 actively exploited?
CVE-2026-11946 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 30.6% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-11946?
CVE-2026-11946 has a CVSS v3 base score of 7.5 (NVD).
How do I remediate CVE-2026-11946?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-11946, 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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