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.
History

Tue, 13 Jan 2026 09:30:00 +0000

Type Values Removed Values Added
First Time appeared Sigstore
Sigstore fulcio
Vendors & Products Sigstore
Sigstore fulcio

Mon, 12 Jan 2026 22:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Mon, 12 Jan 2026 21:15:00 +0000

Type Values Removed Values Added
Description 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.
Title Fulcio vulnerable to Server-Side Request Forgery (SSRF) via MetaIssuer Regex Bypass
Weaknesses CWE-918
References
Metrics cvssV3_1

{'score': 5.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-01-12T21:17:31.478Z

Reserved: 2026-01-09T18:27:19.387Z

Link: CVE-2026-22772

cve-icon Vulnrichment

Updated: 2026-01-12T21:17:14.304Z

cve-icon NVD

Status : Received

Published: 2026-01-12T21:15:59.457

Modified: 2026-01-12T21:15:59.457

Link: CVE-2026-22772

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-01-13T09:27:15Z