CVE-2026-51536

CRITICALPre-NVD 9.19.1—
EchelonGraph scoreHIGH confidence

Score 9.1 from GitHub Security Advisory (severity: CRITICAL) published 2026-07-14. CISA-ADP (Vulnrichment) CVSS v3.1 baseline 9.1; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cisa-adp, epss, ghsa
Trending — 3 sources updated this weekElevated
9.1EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 9.1Exploit: Elevated riskExposed: 0

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

In OpENer 2.3.0 (commit 76b95cf) when parsing incoming CIP (Common Industrial Protocol) network packets, the length parameter is inconsistently typed across the call stack. Specifically, an upstream length calculated as an int is passed to a downstream function that expects an EipInt16 (a 16-bit signed integer). If a maliciously crafted packet with specific length fields is processed, the length parameter can overflow or be truncated into a negative value. This negative length bypasses subsequent bounds checking (due to signed/unsigned comparison issues) and is ultimately used in memory operations, leading to a Stack Buffer Overflow when reading data in DecodePaddedEPath.

CVSS v3
9.1
EG Score
9.1(high)
EG Risk
72(Attend)
EG Risk 72/100SSVC: Attend

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
Severity91% × 45%
Exploitation40% × 40%
Automatability100% × 15%
Action: Remediate soon — notable exploitation risk.
EPSS PROB
0%
EPSS %ILE
38%
KEV
Not listed

Published

July 13, 2026

Last Modified

July 15, 2026

Advisory Details (2)

Auto-updated Jul 14, 2026
No patch confirmed yet.
generic

CVE-2026-51536 · GitHub

https://gist.github.com/MrAlaskan/e160c626a32e03e5d9eddaa732560672
generic

Integer Overflow and Truncation Leading to Stack Buffer Overflow in CIP Message Router · Issue #563 · EIPStackGroup/OpENer · GitHub

https://github.com/EIPStackGroup/OpENer/issues/563

Vendor Advisories for CVE-2026-51536(1)

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

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 27× in last 7d / 47× 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. 2026-07-29 01:05 UTCGHSA enrichment
  2. 2026-07-28 21:08 UTCGHSA enrichment
  3. 2026-07-28 17:11 UTCEG score recompute
  4. 2026-07-28 17:11 UTCGHSA enrichment
  5. 2026-07-28 15:37 UTCEPSS rescore
  6. 2026-07-28 12:25 UTCGHSA enrichment
  7. 2026-07-28 08:25 UTCGHSA enrichment
  8. 2026-07-28 04:26 UTCGHSA enrichment
  9. 2026-07-28 00:29 UTCGHSA enrichment
  10. 2026-07-27 19:53 UTCGHSA enrichment
  11. 2026-07-27 15:44 UTCEG score recompute
  12. 2026-07-27 15:44 UTCGHSA enrichment
  13. 2026-07-27 11:46 UTCGHSA enrichment
  14. 2026-07-27 07:49 UTCGHSA enrichment
  15. 2026-07-27 03:50 UTCGHSA enrichment
  16. 2026-07-26 23:53 UTCGHSA enrichment
  17. 2026-07-26 19:55 UTCGHSA enrichment
  18. 2026-07-26 15:57 UTCEG score recompute
  19. 2026-07-26 15:57 UTCGHSA enrichment
  20. 2026-07-26 14:54 UTCEPSS rescore
  21. 2026-07-26 12:00 UTCEG score recompute
  22. 2026-07-26 12:00 UTCGHSA enrichment
  23. 2026-07-25 14:18 UTCEPSS rescore
  24. 2026-07-24 14:18 UTCEPSS rescore
  25. 2026-07-23 14:18 UTCEPSS rescore
Show 22 more
  1. 2026-07-23 03:19 UTCEG score recompute
  2. 2026-07-22 14:08 UTCEPSS rescore
  3. 2026-07-21 15:25 UTCEPSS rescore
  4. 2026-07-20 17:08 UTCEPSS rescore
  5. 2026-07-19 14:31 UTCEPSS rescore
  6. 2026-07-19 14:31 UTCEPSS rescore
  7. 2026-07-19 02:29 UTCEPSS rescore
  8. 2026-07-18 10:04 UTCEPSS rescore
  9. 2026-07-17 06:05 UTCGHSA enrichment
  10. 2026-07-17 02:07 UTCGHSA enrichment
  11. 2026-07-16 22:08 UTCGHSA enrichment
  12. 2026-07-16 18:11 UTCEG score recompute▲ 9.10
  13. 2026-07-16 18:11 UTCGHSA enrichment
  14. 2026-07-16 17:03 UTCEPSS rescore
  15. 2026-07-15 16:57 UTCEPSS rescore
  16. 2026-07-15 16:57 UTCEPSS rescore
  17. 2026-07-15 02:00 UTCEPSS rescore
  18. 2026-07-15 02:00 UTCEPSS rescore
  19. 2026-07-14 13:45 UTCMITRE cvelistV5CVSS v3 → 9.1 · severity → CRITICAL
  20. 2026-07-13 22:28 UTCNVD update
  21. 2026-07-13 21:44 UTCEG score recompute
  22. 2026-07-13 21:42 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-51536?
CVE-2026-51536 is a critical vulnerability published on July 13, 2026. In OpENer 2.3.0 (commit 76b95cf) when parsing incoming CIP (Common Industrial Protocol) network packets, the length parameter is inconsistently typed across the call stack. Specifically, an upstream length calculated as an int is passed to a downstream function that expects an EipInt16 (a 16-bit…
When was CVE-2026-51536 disclosed?
CVE-2026-51536 was first published in the National Vulnerability Database on July 13, 2026, with the most recent update on July 15, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-51536 actively exploited?
CVE-2026-51536 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 61.7% of all scored CVEs.
What is the CVSS score of CVE-2026-51536?
CVE-2026-51536 has a CVSS v3.1 base score of 9.1 (CISA-ADP / Vulnrichment enrichment; NVD's own analysis pending).
How do I remediate CVE-2026-51536?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-51536, 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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