CVE-2026-45781
Deferred
Deferred - Pending Action
BaseFortify
Vulnerability report for CVE-2026-45781, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-05-14
Last updated on: 2026-05-16
Assigner: GitHub, Inc.
Description
Description
The MCP Registry provides MCP clients with a list of MCP servers, like an app store for MCP servers. Prior to 1.7.9, OCI ownership validation skips label-match check when upstream OCI registry returns HTTP 429, letting any authenticated publisher bind their io.github.<user>/* namespace to OCI images they do not control. internal/validators/registries/oci.go:104-119 fails open on http.StatusTooManyRequests: when the registry's anonymous fetch to the upstream OCI registry is rate-limited, ValidateOCI returns nil and the publish is accepted without ever running the io.modelcontextprotocol.server.name label-match check at lines 122-141. That label check is the only cross-system ownership proof the registry applies to OCI packages — every other registry type (NPM, PyPI, NuGet, MCPB) treats a non-200 upstream response as a hard error. This vulnerability is fixed in 1.7.9.
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
Currently, no data is known.
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-636 | When the product encounters an error condition or failure, its design requires it to fall back to a state that is less secure than other options that are available, such as selecting the weakest encryption algorithm or using the most permissive access control restrictions. |
