Oracle WebLogic Server Unspecified Vulnerability (CVE-2023-21839)

Oracle WebLogic Server contains an unspecified vulnerability that allows an unauthenticated attacker with network access via T3, IIOP, to compromise Oracle WebLogic Server.

Published Jan 18, 2023 · Updated May 29, 2026

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Why patchRisk explained in plain English

Worst-case scenarioIf unpatched

A remote attacker, without authentication, can achieve full data confidentiality loss. Federal agencies are required to remediate by 2023-05-22 under CISA BOD 22-01.

How the attack worksNo clicks needed

This is a Deserialization of Untrusted Data (CWE-502) vulnerability in Oracle WebLogic Server. Vulnerability in the Oracle WebLogic Server product of Oracle Fusion Middleware (component: Core). Supported versions that are affected are 12.2.1.3.0, 12.2.1.4.0 and 14.1.1.0.0. Easily exploitable vulnerability allows unauthenticated attacker with network access via T3, IIOP to compromise Oracle WebLogic Server. Successful attacks of this vulnerability can result in unauthorized access to critical data or complete access to all Oracle WebLogic Server accessible data. CVSS 3.1 Base Score 7.5 (Confidentiality impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N). Exploitation requires remote network access, low attack complexity, no authentication required, and no user interaction required.

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Phishing link

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Malicious file

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Server compromised

Am I affected?Quick check

Probably yes if any of these apply:

●IT Security

●Running weblogic server: 12.2.1.3.0, 12.2.1.4.0, 14.1.1.0.0

Real-world incidentsWhat we've seen

Active exploitation documented in the wild. Threat-research write-up: http://packetstormsecurity.com/files/172882/Oracle-Weblogic-PreAuth-Remote-Command-Execution.html

How to patch

Get the fix

Apply the fixed package from your vendor. The advisory lists affected versions and the exact fixed build.

↗ Vendor advisory

Manual remediation steps