CVE-2026-54430CWE-918

Server-Site Request Forgery in liboauth2

Medium · published July 2, 2026

CVSS v4.0
5.1
EPSS
0%
Percentile
5.9
In the wild
Unconfirmed
What it is

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

The record
Technical detail
CVSS v4.0
5.1 · MEDIUM
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
EPSS
0.00169 · 5.9th percentile
Weakness
CWE-918 · Server-Side Request Forgery (SSRF)
Published
2026-07-02T10:30Z
EPSS history
Timeline
  • 02 JUL 10:30Z
    Server-Site Request Forgery in liboauth2
    cvelistv5