GitHub Advisoryadvisory · Go

GHSA-f83f-xpx7-ffpw Fulcio allocates excessive memory during token parsing

HIGH Published 2025-12-05 Modified 2025-12-05 Official page ↗
Aliases
CVE-2025-66506
Ecosystem
Go
Packages
github.com/sigstore/fulcio
Severity
High
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weaknesses
CWE-405
Reviewed
2025-12-05

Affected packages

• Go github.com/sigstore/fulcio: < 1.8.3 → fixed in 1.8.3

Description

Function identity.extractIssuerURL currently 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. Relevant weakness: CWE-405: Asymmetric Resource Consumption (Amplification) Details See identity.extractIssuerURL Impact Excessive memory allocation

Related

Alias · CVE (1)

  • CVE-2025-66506 Fulcio is a free-to-use certificate authority for issuing code signing certificates for an OpenID Connect (OIDC) identity. vulnerability

Weakness · CWE (1)

  • CWE-405 Asymmetric Resource Consumption (Amplification) weakness

References