CVE-2026-49478

Published: Aug 13, 2026Modified: Sep 9, 2026Deferred

8.7

Vector

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N

Exploitability: 2.2 / Impact: 5.8

Source: security-advisories@github.com (Secondary)

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.

Related CWEs

CWE-918

Server-Side Request Forgery (SSRF)

The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination.

References (4)

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

Source: security-advisories@github.com

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

Source: security-advisories@github.com

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

Source: security-advisories@github.com

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

Source: security-advisories@github.com

Timeline

No history available yet.