CVE-2026-49478

Description

Fulcio is a certificate authority for issuing code signing certificates for an OpenID Connect (OIDC) identity. Versions through 1.8.5 improperly follow cross-host redirects and attach Kubernetes ServiceAccount tokens during OIDC discovery, allowing a malicious or compromised issuer to perform blind SSRF, substitute and cache malicious JWKS keys, or disclose ServiceAccount tokens to external hosts. Version 1.8.6 blocks cross-host redirects, restricts token injection, and restricts local token loading. No known workarounds are available.

References

https://github.com/sm-ard/devops-pulse

https://github.com/sigstore/fulcio/security/advisories/GHSA-f5mr-q85p-6hh6

https://github.com/sigstore/fulcio/releases/tag/v1.8.6

https://github.com/sigstore/fulcio/pull/2354

https://github.com/sigstore/fulcio/commit/378c654f48c3bafdced04ead7010aab2cb4c6ca1

https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-57859

Details

Source: Mitre, NVD

Named Vulnerability: GO-2026-5853Named Vulnerability: GHSA-f5mr-q85p-6hh6

Risk Information

CVSS v2

CVSS v3

EPSS