CVE-2026-49451

HIGHPre-NVD 7.57.5—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 7.5 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.7%, top 52% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, secondary
7.5
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 1%CVSS: 7.5Exploit: NoneExposed: 0

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

The OpenAPI.NET SDK contains a useful object model for OpenAPI documents in .NET along with common serializers to extract raw OpenAPI JSON and YAML documents from the model. From 2.0.0-preview11 until 2.7.5 and 3.5.4, a small OpenAPI document containing a circular schema reference can cause process termination through stack overflow in Microsoft.OpenApi. The issue affects OpenAPI document parsing through public OpenAPI.NET reader APIs and has been confirmed across both JSON and YAML reader paths. This vulnerability is fixed in 2.7.5 and 3.5.4.

CVSS v3
7.5
EG Score
7.5(medium)
EPSS
48.5%
KEV
Not listed

Published

June 30, 2026

Last Modified

July 2, 2026

Advisory Details (1)

Auto-updated Jun 30, 2026
Patch available. Sources: github.
github Patch Available

Circular schema references may terminate OpenAPI parsing · Advisory · microsoft/OpenAPI.NET · GitHub

https://github.com/microsoft/OpenAPI.NET/security/advisories/GHSA-v5pm-xwqc-g5wc

Vendor Advisories for CVE-2026-49451(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 18× in last 7d / 18× 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. 2026-07-07 06:50 UTCEG score recompute
  2. 2026-07-06 17:39 UTCEG score recompute
  3. 2026-07-06 16:27 UTCEPSS rescore
  4. 2026-07-06 04:26 UTCEG score recompute
  5. 2026-07-06 02:23 UTCEPSS rescore
  6. 2026-07-05 15:05 UTCEG score recompute
  7. 2026-07-05 02:30 UTCEPSS rescore
  8. 2026-07-05 01:54 UTCEG score recompute
  9. 2026-07-04 12:44 UTCEG score recompute
  10. 2026-07-04 06:31 UTCEPSS rescore
  11. 2026-07-03 23:34 UTCEG score recompute
  12. 2026-07-03 10:25 UTCEG score recompute
  13. 2026-07-02 21:13 UTCEG score recompute
  14. 2026-07-02 08:03 UTCEG score recompute
  15. 2026-07-01 18:52 UTCEG score recompute
  16. 2026-07-01 15:07 UTCEPSS rescore
  17. 2026-07-01 05:42 UTCEG score recompute
  18. 2026-06-30 16:31 UTCEG score recompute

Frequently asked(5)

What is CVE-2026-49451?
CVE-2026-49451 is a high vulnerability published on June 30, 2026. The OpenAPI.NET SDK contains a useful object model for OpenAPI documents in .NET along with common serializers to extract raw OpenAPI JSON and YAML documents from the model. From 2.0.0-preview11 until 2.7.5 and 3.5.4, a small OpenAPI document containing a circular schema reference can cause process…
When was CVE-2026-49451 disclosed?
CVE-2026-49451 was first published in the National Vulnerability Database on June 30, 2026, with the most recent update 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-2026-49451 actively exploited?
CVE-2026-49451 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 48.5% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-49451?
CVE-2026-49451 has a CVSS v3 base score of 7.5 (NVD).
How do I remediate CVE-2026-49451?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-49451, 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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