Improper Ownership Validation in MCP Registry Affects Multiple Clients
CVE-2026-45781

3.5LOW

Key Information:

Vendor

Modelcontextprotocol

Status
Registry
Vendor
CVE Published:
14 May 2026

What is CVE-2026-45781?

The MCP Registry, functioning as a catalog for MCP servers, faced a significant vulnerability that allowed authentication-validated publishers to associate their namespaces with uncontrolled OCI images. This occurred prior to version 1.7.9 due to an oversight where an HTTP 429 (Too Many Requests) response from the upstream OCI registry bypassed essential label checks intended for ownership validation. The internal code designed to validate the ownership status failed when encountering these rate-limiting responses, mistakenly accepting potentially unauthorized publish requests without enforcing the critical label-match requirement. The flaw exposes the integrity of namespace mappings, risking unwanted associations across multiple systems. The vulnerability has since been resolved in version 1.7.9 of the MCP Registry.

Affected Version(s)

registry < 1.7.9

References

https://github.com/modelcontextprotocol/registry/security...
x_refsource_CONFIRM

CVSS V3.1

Score:
3.5
Severity:
LOW
Confidentiality:
None
Integrity:
Low
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
Low
User Interaction:
Required
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.