Apache Dubbo up to 2.6.9/2.7.9 Telnet deserialization

Summaryinfo

A vulnerability marked as very critical has been reported in Apache Dubbo up to 2.6.9/2.7.9. Affected by this vulnerability is an unknown functionality of the component Telnet Handler. Performing a manipulation results in deserialization. This vulnerability is known as CVE-2021-32824. Remote exploitation of the attack is possible. No exploit is available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability classified as very critical has been found in Apache Dubbo up to 2.6.9/2.7.9. This affects an unknown code of the component Telnet Handler. The manipulation with an unknown input leads to a deserialization vulnerability. CWE is classifying the issue as CWE-502. The product deserializes untrusted data without sufficiently verifying that the resulting data will be valid. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

Apache Dubbo is a java based, open source RPC framework. Versions prior to 2.6.10 and 2.7.10 are vulnerable to pre-auth remote code execution via arbitrary bean manipulation in the Telnet handler. The Dubbo main service port can be used to access a Telnet Handler which offers some basic methods to collect information about the providers and methods exposed by the service and it can even allow to shutdown the service. This endpoint is unprotected. Additionally, a provider method can be invoked using the `invoke` handler. This handler uses a safe version of FastJson to process the call arguments. However, the resulting list is later processed with `PojoUtils.realize` which can be used to instantiate arbitrary classes and invoke its setters. Even though FastJson is properly protected with a default blocklist, `PojoUtils.realize` is not, and an attacker can leverage that to achieve remote code execution. Versions 2.6.10 and 2.7.10 contain fixes for this issue.

The weakness was published 01/03/2023 by shutdown as GHSL-2021-034. The advisory is shared at securitylab.github.com. This vulnerability is uniquely identified as CVE-2021-32824 since 05/12/2021. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 01/27/2023).

Upgrading to version 2.6.10 or 2.7.10 eliminates this vulnerability.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Vendor

• Apache

Name

• Dubbo

Version

• 2.6.0
• 2.6.1
• 2.6.2
• 2.6.3
• 2.6.4
• 2.6.5
• 2.6.6
• 2.6.7
• 2.6.8
• 2.6.9
• 2.7.0
• 2.7.1
• 2.7.2
• 2.7.3
• 2.7.4
• 2.7.5
• 2.7.6
• 2.7.7
• 2.7.8
• 2.7.9

License

• open-source

Website

• Vendor: https://www.apache.org/

CPE 2.3info

• 🔍
• 🔍
• 🔍

CPE 2.2info

• 🔍
• 🔍
• 🔍

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Discussion