CVE-2026-22772

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.

CVSS v3 5.8 MEDIUM

5.8^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/sigstore/fulcio/commit/eaae2f2be56df9dea5f9b439ec81bedae4c0978d	Patch
https://github.com/sigstore/fulcio/security/advisories/GHSA-59jp-pj84-45mr	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:linuxfoundation:fulcio:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-01-12 21:15

Updated : 2026-03-05 13:48

NVD link : CVE-2026-22772

Mitre link : CVE-2026-22772

CVE.ORG link : CVE-2026-22772

JSON object : View

Products Affected

linuxfoundation

fulcio

CWE

CWE-918

Server-Side Request Forgery (SSRF)

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