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Security Advisories

CVE-2025-66506

NVD

https://nvd.nist.gov/vuln/detail/CVE-2025-66506

Severity

7.5

High

CVSS V3

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Summary

Fulcio allocates excessive memory during token parsing

Description

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

Affected packages

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