CVE-2026-108698

hyper-mcp through 0.8.3 contains a signature verification bypass vulnerability in load_wasm in src/wasm/oci.rs that verifies the Cosign signature of a separately resolved tag rather than the loaded manifest. Attackers controlling registry responses for the tag can serve an unsigned malicious manifest to the loader and a signed one to Cosign, executing unsigned WebAssembly plugins with configured host capabilities.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 4.2

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/hyper-mcp-rs/hyper-mcp
https://github.com/hyper-mcp-rs/hyper-mcp/blob/v0.8.3/src/wasm/oci.rs#L193-L224
https://github.com/hyper-mcp-rs/hyper-mcp/blob/v0.8.3/src/wasm/oci.rs#L79-L148
https://hackmd.io/@1ExmmukzRMWN7B4gQ4W-4Q/hyper-mcp-oci-signature-manifest-toctou
https://www.vulncheck.com/advisories/hyper-mcp-through-0.8.3-oci-plugin-signature-verification-toctou-race-condition

Configurations

No configuration.

History

11 Oct 2026, 14:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-11 14:17

Updated : 2026-10-16 19:18

NVD link : CVE-2026-108698

Mitre link : CVE-2026-108698

CVE.ORG link : CVE-2026-108698

JSON object : View

Products Affected

No product.

CWE

CWE-367

Time-of-check Time-of-use (TOCTOU) Race Condition

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