CVE-2020-2551 Oracle Fusion Middleware Unspecified

Exploited in the wild Critical 9.8 Published 15 Jan 2020 Updated 12 Jan 2026

Unauthenticated attackers can achieve remote code execution and full server takeover via IIOP deserialization flaws in Oracle WebLogic Server.

Exploited in the wild: Since 16 Nov 2023
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: None listed

What is CVE-2020-2551?

CVE-2020-2551 is a critical unsafe deserialization vulnerability in Oracle Weblogic Server, published on 15 Jan 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

Vulnerability in the Oracle WebLogic Server product of Oracle Fusion Middleware (component: WLS Core Components). Supported versions that are affected are 10.3.6.0.0, 12.1.3.0.0, 12.2.1.3.0 and 12.2.1.4.0. Easily exploitable vulnerability allows unauthenticated attacker with network access via IIOP to compromise Oracle WebLogic Server. Successful attacks of this vulnerability can result in takeover of Oracle WebLogic Server. CVSS 3.0 Base Score 9.8 (Confidentiality, Integrity and Availability impacts). CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H).

Which versions are affected by CVE-2020-2551?

It affects 1 product.

Products include Oracle Weblogic Server.

How do I fix CVE-2020-2551?

No fix has been published for CVE-2020-2551 yet. Limit exposure of the affected software until one is available. US federal agencies must fix it by 7 Dec 2023.

Upgrade, and only deserialise data from trusted sources or with an allow-list of types. More about Unsafe deserialization.

Is CVE-2020-2551 being exploited?

Yes. Attackers have exploited CVE-2020-2551 in the wild since at least 16 Nov 2023.

Public exploit code: 1 Nuclei template and 8 proofs of concept on GitHub.

All Oracle Weblogic Server vulnerabilities

Sources

Also known as GHSA-85qx-3cmc-hcq4.