Signature Verification Bypass in Hyper-mcp Affects WebAssembly Plugin Security

CVE-2026-108698

What is CVE-2026-108698?

The hyper-mcp product up to version 0.8.3 contains a critical flaw where the signature verification process can be bypassed. This occurs in the load_wasm function, which mistakenly verifies the Cosign signature of a tag that has been resolved separately, rather than the actual loaded manifest. As a result, hackers with control over registry responses can deliver an unsigned malicious manifest while serving a signed one to Cosign. This enables unauthorized execution of unsigned WebAssembly plugins with the privileges configured by the host, potentially compromising system security.

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