Is CVE-2026-45781 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-45781 being exploited in the wild.

How severe is CVE-2026-45781?

Low severity, with a CVSS score of 3.5, published 14 May 2026.

Which products and versions are affected?

github.com/modelcontextprotocol/registry (Go) < 1.7.9, SEMVER:introduced=0,fixed=1.7.9; Model Context Protocol MCP Registry < 1.7.9; Model Context Protocol Registry < 1.7.9.

Is there a fix for CVE-2026-45781?

Yes. github.com/modelcontextprotocol/registry (Go): upgrade to 1.7.9 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-45781 attacked?

It is attacked over the network, in a hosted service.

Am I affected by CVE-2026-45781?

Check whether you run github.com/modelcontextprotocol/registry (Go), Model Context Protocol MCP Registry or Model Context Protocol Registry at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-45781: Model Context Protocol Registry ownership bypass in OCI validator

Q: Is there a fix for CVE-2026-45781?

Yes. github.com/modelcontextprotocol/registry (Go): upgrade to 1.7.9 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

Q: How is CVE-2026-45781 attacked?

It is attacked over the network, in a hosted service.

Q: Am I affected by CVE-2026-45781?

Check whether you run github.com/modelcontextprotocol/registry (Go), Model Context Protocol MCP Registry or Model Context Protocol Registry at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-45781 · Severity: low · CVSS 3.5 · Published 2026-05-14

The Model Context Protocol (MCP) Registry, which helps users discover and use AI-related server tools, contains a flaw in how it verifies ownership of container images. When the registry is busy or being intentionally flooded with requests, it may skip security checks that confirm a publisher actually owns the image they are listing. This allows an attacker to list reputable third-party software under their own name, potentially misleading users through impersonation or typo-squatting.

Technologies: github.com/modelcontextprotocol/registry (Go), Model Context Protocol Registry. Vendors: Go, Model Context Protocol.

Quick answers

Is CVE-2026-45781 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-45781 being exploited in the wild.
How severe is CVE-2026-45781?: Low severity, with a CVSS score of 3.5, published 14 May 2026.
Which products and versions are affected?: github.com/modelcontextprotocol/registry (Go) < 1.7.9, SEMVER:introduced=0,fixed=1.7.9; Model Context Protocol MCP Registry < 1.7.9; Model Context Protocol Registry < 1.7.9.
Is there a fix for CVE-2026-45781?: Yes. github.com/modelcontextprotocol/registry (Go): upgrade to 1.7.9 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-45781 attacked?: It is attacked over the network, in a hosted service.
Am I affected by CVE-2026-45781?: Check whether you run github.com/modelcontextprotocol/registry (Go), Model Context Protocol MCP Registry or Model Context Protocol Registry at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

github.com/modelcontextprotocol/registry (Go): upgrade to 1.7.9 or later
```
go get github.com/modelcontextprotocol/registry@v1.7.9
```

Technical details

The vulnerability exists in `internal/validators/registries/oci.go` where the `ValidateOCI` function returns `nil` (success) when a `http.StatusTooManyRequests` (429) error is received from an upstream OCI registry like Docker Hub. This 'fail-open' behavior bypasses the mandatory `io.modelcontextprotocol.server.name` label-match check, which is the primary mechanism for proving image ownership. An attacker can intentionally trigger this state by exhausting the registry's anonymous Docker Hub quota (100 pulls/6h) through rapid `/publish` requests. Once the quota is exhausted, the attacker can successfully publish a server record that points to any public OCI image they do not control. The issue is fixed in version 1.7.9 by treating rate limits as a validation error.

Affected products

modelcontextprotocol registry < 1.7.9

Identifiers

CVE-2026-45781
GHSA-2v5f-5r6w-p67r
GO-2026-5008

Timeline

2026-05-09: other: Vulnerability identified in commit fe0cb3b
2026-05-12: disclosed: Reported via GitHub Private Security Advisory
2026-05-19: patched: Fix released in version 1.7.9
2026-05-19: advisory

References

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