CVE-2026-49478

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.

CVSS v3 8.7 HIGH

8.7^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 5.8

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/sigstore/fulcio/commit/378c654f48c3bafdced04ead7010aab2cb4c6ca1
https://github.com/sigstore/fulcio/pull/2354
https://github.com/sigstore/fulcio/releases/tag/v1.8.6
https://github.com/sigstore/fulcio/security/advisories/GHSA-f5mr-q85p-6hh6

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-13 13:19

Updated : 2026-09-09 21:02

NVD link : CVE-2026-49478

Mitre link : CVE-2026-49478

CVE.ORG link : CVE-2026-49478

JSON object : View

Products Affected

No product.

CWE

CWE-918

Server-Side Request Forgery (SSRF)

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