CVE-2026-22772Fulcio vulnerable to Server-Side Request Forgery (SSRF) via MetaIssuer Regex Bypass

Descripción

Fulcio is a certificate authority for issuing code signing certificates for an OpenID Connect (OIDC) identity. Prior to 1.8.5, Fulcio's metaRegex() function uses unanchored regex, allowing attackers to bypass MetaIssuer URL validation and trigger SSRF to arbitrary internal services. Since the SSRF only can trigger GET requests, the request cannot mutate state. The response from the GET request is not returned to the caller so data exfiltration is not possible. A malicious actor could attempt to probe an internal network through Blind SSRF. This vulnerability is fixed in 1.8.5.

Datos: CVE.org, NVD, CISA KEV, FIRST EPSS, Ubuntu. Se publican tal como los indican las fuentes, en inglés.

Productos y versiones afectados

Referencias y parches

• https://github.com/sigstore/fulcio/security/advisories/GHSA-59jp-pj84-45mr ExploitVendor Advisory
• https://github.com/sigstore/fulcio/commit/eaae2f2be56df9dea5f9b439ec81bedae4c0978d Patch