CVE-2026-51540

CRITICALPre-NVD 9.8Trending — 4 sources updated this weekElevated
9.8
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 0%CVSS: 9.8Exploit: NoneExposed: 0

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

OpENer 2.3.0 (master branch up to commit 76b95cf) is vulnerable to a severe memory corruption issue caused by an integer underflow in the processing of connected explicit messages (SendUnitData).

CVSS v3
9.8
EG Score
0.0(none)
EPSS
30.1%
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

Integer Underflow Leading to Stack Buffer Overflow in CIP Connected Message Path · Issue #568 · EIPStackGroup/OpENer · GitHub

https://github.com/EIPStackGroup/OpENer/issues/568
generic

CVE-2026-51540 · GitHub

https://gist.github.com/MrAlaskan/5e0c2af7f4a1d188814c7fa8f812c8da

Vendor Advisories for CVE-2026-51540(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 8× in last 7d / 8× 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. 2026-07-15 16:57 UTCEPSS rescore
  2. 2026-07-15 16:57 UTCEPSS rescore
  3. 2026-07-15 02:00 UTCEPSS rescore
  4. 2026-07-15 02:00 UTCEPSS rescore
  5. 2026-07-14 16:40 UTCMITRE cvelistV5CVSS v3 → 9.8 · severity → CRITICAL
  6. 2026-07-13 22:28 UTCNVD update
  7. 2026-07-13 22:03 UTCEG score recompute
  8. 2026-07-13 22:02 UTCMITRE cvelistV5first tracked

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-51540?
CVE-2026-51540 is a critical vulnerability published on July 13, 2026. OpENer 2.3.0 (master branch up to commit 76b95cf) is vulnerable to a severe memory corruption issue caused by an integer underflow in the processing of connected explicit messages (SendUnitData).
When was CVE-2026-51540 disclosed?
CVE-2026-51540 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-2026-51540 actively exploited?
CVE-2026-51540 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 30.1% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-51540?
CVE-2026-51540 has a CVSS v3.1 base score of 9.8 (CISA-ADP / Vulnrichment enrichment; NVD's own analysis pending). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 0.0.
How do I remediate CVE-2026-51540?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-51540, 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

Explore the affected products and dependency analysis for CVE-2026-51540

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