CVE-2019-17564 Scanner

Apache Dubbo is an open-source RPC framework used predominantly by microservices applications. It is widely deployed in various companies to facilitate remote service calls due to its efficiency and scalability. Organizations favor Dubbo for its performance since it seamlessly manages distributed systems communication in large-scale operations. It is mainly employed in the backend of e-commerce platforms, fintech applications, and other sectors needing robust service governance capabilities. The ease of integration with multiple language ecosystems and support for different serialization protocols makes it versatile. This adaptability, coupled with a strong community and consistent updates, has contributed to its significance in modern application infrastructures.

Deserialization of Untrusted Data refers to the vulnerability where an attacker submits data for deserialization without sufficient security checks. This particular type of vulnerability can allow attackers to execute arbitrary code when an application deserializes untrusted data from unreliable sources. In Apache Dubbo, improper handling during the deserialization process leads to potential remote code execution. Mismanagement of byte streams can result in invoked undesired classes or code paths, leading to a system compromise. The vulnerability is related to the incorrect or poor implementation of deserialization logic with minimal validation checks to secure the deserialized objects.

In this case, the vulnerability took place due to unsafe deserialization in Dubbo applications with HTTP remoting enabled. An endpoint accepting Java objects over the network through POST requests becomes the vector for this issue. Attackers target instances of Apache Dubbo that have HTTP enabled, by sending crafted Java objects, exploiting the absence of security checks. The application's failure to validate the integrity and authenticity of serialized objects allows arbitrary remote code execution. Malicious actors can bypass existing authorization mechanisms and exploit deserialization to initiate harmful operations on the remote server, compromising its integrity.

Exploitation of deserialization vulnerabilities can lead to severe full-system compromises. Attackers can obtain unauthorized access to sensitive data, control network infrastructure, or propagate further malware through the exploited systems. The systems' confidentiality, integrity, and availability can be significantly impacted, resulting in data breaches, operational disruption, or even financial losses. It poses a critical threat where malicious payloads may bring down systems or even extract information silently. Such vulnerabilities, if exploited, could severely tarnish an organization’s reputation due to the data leakages or service outages.

REFERENCES

• https://advisory.checkmarx.net/advisory/CX-2020-4275
• https://github.com/Hu3sky/CVE-2019-17564
• https://github.com/r00t4dm/CVE-2019-17564
• https://dubbo.apache.org/en/docs3-v2/java-sdk/advanced-features-and-usage/security/