CVE-2026-54430 Server-Site Request Forgery in liboauth2
An attacker can force the server to send requests to internal paths via unsanitized JWT headers in liboauth2, potentially accessing internal resources.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-54430?
CVE-2026-54430 is a medium-severity server-side request forgery vulnerability in OpenIDC liboauth2, published on 2 Jul 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official 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
Weakness: CWE-918
Which versions are affected by CVE-2026-54430?
How do I fix CVE-2026-54430?
Upgrade to a fixed version.
Upgrade, and send outbound requests through an allow-list that blocks internal addresses. More about Server-side request forgery.
Is CVE-2026-54430 being exploited?
There is no known exploitation of CVE-2026-54430 in the wild and no public exploit code.
Sources
Also known as AZL-91679, DEBIAN-CVE-2026-54430, GHSA-qrcr-3862-9f4c, UBUNTU-CVE-2026-54430.