CVE-2026-54430

Publication date 3 July 2026

Last updated 4 July 2026


Ubuntu priority

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

Status

Package Ubuntu Release Status
liboauth2 26.04 LTS resolute
Needs evaluation
25.10 questing
Needs evaluation
24.04 LTS noble
Needs evaluation
22.04 LTS jammy
Needs evaluation

Severity score breakdown

CVSS version: CVSS v4.0

Base score 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


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