Vulnerability Description
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 Score
HIGH
Related Weaknesses (CWE)
References
- https://github.com/microsoft/OpenAPI.NET/security/advisories/GHSA-v5pm-xwqc-g5wc
- https://github.com/microsoft/OpenAPI.NET/security/advisories/GHSA-v5pm-xwqc-g5wc
FAQ
What is CVE-2026-49451?
CVE-2026-49451 is a vulnerability with a CVSS score of 7.5 (HIGH). 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...
How severe is CVE-2026-49451?
CVE-2026-49451 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-49451?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.