What is the CVSS score of CVE-2026-45781?

CVE-2026-45781 has a CVSS 3.1 base score of 3.5 (Low). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N. EPSS exploitation probability: 0.0%.

Which versions of MCP Registry are affected by CVE-2026-45781?

Improper ownership validation in MCP Registry prior to version 1.7.9 allows authenticated publishers to bind io.github. /* namespaces to OCI images they do not control when the upstream OCI…. A patch is available.

Is there a patch available for CVE-2026-45781?

Yes, a patch is available for CVE-2026-45781. Update the affected software to the latest version immediately.

MCP Registry CVE-2026-45781

EUVD-2026-30489 LOW

Not Failing Securely ('Failing Open') (CWE-636)

2026-05-14 security-advisories@github.com

GHSA-2v5f-5r6w-p67r

Information Disclosure Node.js

3.5

CVSS 3.1 · GitHub Advisory

Severity by source

GitHub Advisory PRIMARY

3.5 LOW

AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N

Primary rating from GitHub Advisory · only source for this CVE.

CVSS VectorGitHub Advisory

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

Required

Scope

Unchanged

Confidentiality

None

Integrity

Low

Availability

None

Lifecycle Timeline

Analysis Generated

May 14, 2026 - 22:06 vuln.today

Patch available

May 14, 2026 - 22:02 EUVD

CVE Published

May 14, 2026 - 21:16 nvd

LOW 3.5

DescriptionGitHub Advisory

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.

AnalysisAI

Improper ownership validation in MCP Registry prior to version 1.7.9 allows authenticated publishers to bind io.github.<user>/* namespaces to OCI images they do not control when the upstream OCI registry returns HTTP 429 rate-limit responses. The vulnerability bypasses the label-match ownership proof check, enabling namespace hijacking for users who publish through OCI-based MCP servers. Patch available in version 1.7.9.

Technical ContextAI

The MCP Registry validates OCI package ownership by checking the io.modelcontextprotocol.server.name label on the upstream OCI image. The validation logic in internal/validators/registries/oci.go (lines 104-119) performs an anonymous fetch to the upstream OCI registry; however, it fails open when receiving HTTP 429 (Too Many Requests) responses, returning nil without executing the critical label-match check (lines 122-141). This differs from all other registry types (NPM, PyPI, NuGet, MCPB), which treat non-200 upstream responses as hard errors. CWE-636 (Weak Ownership Validation) describes the root cause: the system skips the only cross-system ownership proof mechanism when rate-limited, allowing any authenticated user to claim ownership of namespaces via OCI images they do not control.

RemediationAI

Upgrade MCP Registry to version 1.7.9 or later immediately. The patch modifies internal/validators/registries/oci.go to treat HTTP 429 responses from the upstream OCI registry as hard errors (consistent with other registry types), forcing the label-match check to execute before accepting namespace bindings. No workarounds are available for unpatched versions; the vulnerability is inherent to the validation logic. Organizations unable to upgrade immediately should implement upstream controls: restrict OCI image binding for io.github.* namespaces to a verified allowlist of publishers, or temporarily disable OCI-based MCP server publishing until 1.7.9 is deployed. See vendor advisory at https://github.com/modelcontextprotocol/registry/security/advisories/GHSA-2v5f-5r6w-p67r for confirmation.