CVE-2026-54430

liboauth2 is vulnerable to Server-Side Request Forgery in oauth2_jose_jwks_aws_alb_resolve() function. The AWS ALB verifier reads both signer and kid from the unverified JWT header. If signer matches the configured ARN, kid is appended to alb_base_url without URL encoding or path sanitization, and the HTTP GET is issued before signature verification. This allows an attacker to force the server to send a GET request to an attacker-chosen internal path. This issue was fixed in version 2.3.0

CVSS

No CVSS.

References

Link	Resource
https://cert.pl/en/posts/2026/07/CVE-2026-54430
https://github.com/OpenIDC/liboauth2
https://github.com/OpenIDC/liboauth2/commit/347507ac5b51f48c2933bbe49b2ee07c2af4712b

Configurations

No configuration.

History

No history.

Information

Published : 2026-07-02 11:16

Updated : 2026-07-02 17:43

NVD link : CVE-2026-54430

Mitre link : CVE-2026-54430

CVE.ORG link : CVE-2026-54430

JSON object : View

Products Affected

No product.

CWE

CWE-918

Server-Side Request Forgery (SSRF)

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