{"id":"CVE-2026-108699","title":"hyper-mcp through 0.8.3 contains an improper signature verification vulnerability that allows attackers to load malicious WebAssembly plugins because cosign_verify_args() accepts any signer identity and OIDC issuer by default","summary":"hyper-mcp through 0.8.3 contains an improper signature verification vulnerability that allows attackers to load malicious WebAssembly plugins because cosign_verify_args() accepts any signer identity and OIDC issuer by default. Attackers …","severity":"medium","cvss":6.5,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:H/A:N","cwe":["CWE-347"],"vendor":"hyper-mcp-rs","product":"hyper-mcp","affected":["hyper-mcp <= 0.8.3"],"published":"2026-10-11","updated":"2026-10-16","sourceUpdated":"2026-10-16T19:21:14.417","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-108699","references":[{"url":"https://github.com/hyper-mcp-rs/hyper-mcp","label":"disclosure@vulncheck.com"},{"url":"https://github.com/hyper-mcp-rs/hyper-mcp/blob/v0.8.3/src/config.rs#L138-L170","label":"disclosure@vulncheck.com"},{"url":"https://github.com/hyper-mcp-rs/hyper-mcp/blob/v0.8.3/src/wasm/oci.rs#L157-L190","label":"disclosure@vulncheck.com"},{"url":"https://hackmd.io/@1ExmmukzRMWN7B4gQ4W-4Q/hyper-mcp-oci-signature-manifest-toctou","label":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/hyper-mcp-through-0.8.3-improper-signature-verification-of-oci-webassembly-plugins","label":"disclosure@vulncheck.com"},{"url":"https://hackmd.io/@1ExmmukzRMWN7B4gQ4W-4Q/cve-2026-108698-108699-hyper-mcp-oci-signature-manifest-toctou","label":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}],"tags":["nvd","cve.org","exploit-available"],"epss":0.00169,"epssPercentile":0.06182,"exploitAvailable":true,"ssvc":{"exploitation":"poc","automatable":"no","technicalImpact":"partial","timestamp":"2026-10-13T19:35:14.241288Z"},"ingestedAt":"2026-10-12T14:50:34.050Z","slug":"CVE-2026-108699","body":"## Overview\n\nhyper-mcp through 0.8.3 contains an improper signature verification vulnerability that allows attackers to load malicious WebAssembly plugins because cosign_verify_args() accepts any signer identity and OIDC issuer by default. Attackers controlling a plugin image reference can sign a malicious image with a free Sigstore keyless certificate to execute plugins with configured host, filesystem, and environment capabilities.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":48,"depthScoreParts":{"impact":35.8,"likelihood":0,"exploitation":12,"ransomware":0},"changes":[{"seq":221125,"id":"CVE-2026-108699","ts":1792030752219,"field":"exploit_available","old":"false","new":"true"}]}