CVE catalog

CVE-2025-66506

DEBIAN-CVE-2025-66506

[CVE catalog]

Severity
High · CVSS 7.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Published
Updated
Source
[NVD] · [CVE record]
EPSS
0.21% · Oct 27, 2026

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.

Vulnerable and fixed packages

Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.

DistributionPackageReleaseVersionStatus
Debiangolang-github-sigstore-fulcio131.6.5-1vulnerable
Debiangolang-github-sigstore-fulcio131.7.1-1vulnerable
Debiangolang-github-sigstore-fulcio131.8.5-1vulnerable
Debiangolang-github-sigstore-fulcio131.8.7-1vulnerable
Debiangolang-github-sigstore-fulcio131.8.8-1vulnerable
Debiangolang-github-sigstore-fulcio141.6.5-1vulnerable
Debiangolang-github-sigstore-fulcio141.7.1-1vulnerable
Debiangolang-github-sigstore-fulcio141.8.5-1fixed

Fixed-version evidence

DistributionPackageTypeReleaseFixed versionUrgencyOriginBugs
Debiangolang-github-sigstore-fulciodeb141.8.5-1Not reportedDEBIAN-CVE-2025-66506Not reported

OpenFactory catalog packages

[Debian 13 (Trixie)]

Observed:

References

[FIRST EPSS] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX] · [SUSE security advisories and VEX]