CVE-2026-89058
HIGH
NVD
CVSS Score
7.4
Severity
HIGH
Published
Sep 18, 2026
Vendor
unknown
Description
A flaw was found in RESTEasy's CorsFilter, which, when configured to allow all origins ("*"), reflects the request's Origin header back in the Access-Control-Allow-Origin response together with Access-Control-Allow-Credentials: true. This permissive cross-origin policy allows a malicious website to make credentialed cross-origin requests and read authenticated responses from a victim's session, resulting in a loss of confidentiality.