CVE-2026-21999: Oracle XML Database

Medium severity, CVSS 5.3. EPSS: 0.2% chance of exploitation in the next 30 days.

Vulnerability in the XML Database component of Oracle Database Server. Supported versions that are affected are 23.4.0-23.26.1. Difficult to exploit vulnerability allows unauthenticated attacker with network access via HTTPS to compromise XML Database. Successful attacks require human interaction from a person other than the attacker. Successful attacks of this vulnerability can result in unauthorized access to critical data or complete access to all XML Database accessible data. CVSS 3.1 Base Score 5.3 (Confidentiality impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:N/A:N).

Affected products

• Oracle XML Database: from 23.4, up to and including 23.26.1

Published 2026-04-21. Last modified 2026-07-08.