CVE-2021-36163 Unsafe deserialization in providers using the Hessian protocol

What is CVE-2021-36163?

CVE-2021-36163 is a critical unsafe deserialization vulnerability in Apache Dubbo, published on 7 Sep 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

In Apache Dubbo, users may choose to use the Hessian protocol. The Hessian protocol is implemented on top of HTTP and passes the body of a POST request directly to a HessianSkeleton: New HessianSkeleton are created without any configuration of the serialization factory and therefore without applying the dubbo properties for applying allowed or blocked type lists. In addition, the generic service is always exposed and therefore attackers do not need to figure out a valid service/method name pair. This is fixed in 2.7.13, 2.6.10.1

Weakness: CWE-502

Which versions are affected by CVE-2021-36163?

4 open source packages ship an affected version, including org.apache.dubbo:dubbo. It affects 1 product.

Products include Apache Dubbo.

How do I fix CVE-2021-36163?

Upgrade org.apache.dubbo:dubbo to a fixed version for your release line: 2.6.10.1 or 2.7.13.

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

Is CVE-2021-36163 being exploited?

There is no known exploitation of CVE-2021-36163 in the wild and no public exploit code.

Other vulnerabilities in Apache Dubbo

• CVE-2023-29234 Bypass serialize checks in Apache Dubbo Critical 9.8
• CVE-2023-46279 Apache Dubbo: Bypass deny serialize list check in Apache Dubbo Critical 9.8
• CVE-2021-32824 Regular expression Denial of Service in MooTools Critical 9.8
• CVE-2022-39198 Apache Dubbo Hession Deserialization Vulnerability Gadgets Bypass Critical 9.8
• CVE-2021-43297 Dubbo Hessian cause RCE when parse error Critical 9.8

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-cpx9-4rwv-486v.