CVE-2026-89058

CVE Details

Release Date:	2026-09-18
Impact:	Moderate	What is this?

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.

See more information about CVE-2026-89058 from MITRE CVE dictionary and NIST NVD

NOTE: The following CVSS metrics and score provided are preliminary and subject to review.

CVSS v3 metrics

Base Score:	7.4
Vector String:	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:N/A:N
Version:	3.1
Attack Vector:	Network
Attack Complexity:	Low
Privileges Required:	None
User Interaction:	Required
Scope:	Changed
Confidentiality Impact:	High
Integrity Impact:	None
Availability Impact:	None

Errata information

Platform	Errata	Release Date
Oracle Linux version 9 (resteasy)	ELSA-2026-85234	2026-10-19