CVE-2025-66506 (GCVE-0-2025-66506)
Vulnerability from cvelistv5
Published
2025-12-04 22:04
Modified
2025-12-05 15:32
Severity ?
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
  • CWE-405 - Asymmetric Resource Consumption (Amplification)
Summary
Fulcio is a free-to-use certificate authority for issuing code signing certificates for an OpenID Connect (OIDC) identity. Prior to 1.8.3, function identity.extractIssuerURL splits (via a call to strings.Split) its argument (which is untrusted data) on periods. As a result, in the face of a malicious request with an (invalid) OIDC identity token in the payload containing many period characters, a call to extractIssuerURL incurs allocations to the tune of O(n) bytes (where n stands for the length of the function's argument), with a constant factor of about 16. This vulnerability is fixed in 1.8.3.
References
Impacted products
Vendor Product Version
sigstore fulcio Version: < 1.8.3
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