CVE-2026-108699 (GCVE-0-2026-108699)

Vulnerability from cvelistv5 – Published: 2026-10-11 13:25 – Updated: 2026-10-11 13:25
VLAI
Title
hyper-mcp through 0.8.3 Improper Signature Verification of OCI WebAssembly Plugins
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 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.
Severity
8.3 (High)
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N
6.5 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:H/A:N
CWE
  • CWE-347 - Improper Verification of Cryptographic Signature
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 5802 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
hyper-mcp-rs hyper-mcp Affected: 0 , ≤ 0.8.3 (semver)
guessed Create a notification for this product.
Date Public
2026-10-11 00:00
Credits
hieuPenguinnn
Show details on NVD website
To clipboard 

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              "version": "0",
              "versionType": "semver"
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        }
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  "cveMetadata": {
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    "cveId": "CVE-2026-108699",
    "datePublished": "2026-10-11T13:25:59.469Z",
    "dateReserved": "2026-10-10T23:08:36.419Z",
    "dateUpdated": "2026-10-11T13:25:59.469Z",
    "state": "PUBLISHED"
  },
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          }
        ],
        "id": "CVE-2026-108699",
        "lastModified": "2026-10-11T14:17:04.257",
        "metrics": {
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}



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