Description
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
Severity (CVSS)
| Base score | 5.1 |
|---|---|
| Severity | Medium |
| Version | CVSS 4.0 |
| Vector | CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:L/SI:N/SA:N |
| Provided by | CNA |
Weaknesses
- CWE-918 — CWE-918 Server-Side Request Forgery (SSRF)
Affected products
| Vendor | Product | Versions |
|---|---|---|
| OpenIDC | liboauth2 | 0 to <2.3.0 |
References
- https://cert.pl/en/posts/2026/07/CVE-2026-54430 (third-party-advisory)
- https://github.com/OpenIDC/liboauth2 (product)
- https://github.com/OpenIDC/liboauth2/commit/347507ac5b51f48c2933bbe49b2ee07c2af4712b (issue-tracking)
Generated from the official CVE List on 03 Jul 2026 07:05 UTC.