SSRF in Openidc Liboauth2
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
Vulnerability class: SSRF (Server-Side Request Forgery)
Published · last modified .
EPSS exploit prediction
EPSS: 0.002 (5.6th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 6th percentile — 5.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: 0.000
Affected products
- Openidc Liboauth2 — versions 0
Weakness classification (CWE)
References
- cert.pl/en/posts/2026/06/CVE-2026-54430 (third-party-advisory)
- github.com/OpenIDC/liboauth2 (product)
- github.com/OpenIDC/liboauth2/commit/347507ac5b51f48c2933bbe49b2ee07c2af4712b (issue-tracking)
- cert.pl/en/posts/2026/07/CVE-2026-54430 (third-party-advisory)