CVE-2026-70410: Apache Calcite Avatica: Unrestricted class initialization when instantiating plugins
Use of Externally-Controlled Input to Select Classes or Code ('Unsafe Reflection') vulnerability in Apache Calcite Avatica. Plugin instantiation (via AvaticaUtils#instantiatePlugin and other methods) initializes arbitrary classes via unrestricted calls to Class.forName(String) which by default triggers initialization. This may lead to the execution of static initializer blocks in arbitrary classes present in the classpath. The instantiation APIs should initialize and instantiate only classes implementing the specified plugin interface passed as input in conjunction with the desired classname. At the moment of writing, there are no well-known or widely used classes with dangerous static initializer blocks so the severity is low.
This issue affects Apache Calcite Avatica: before 1.29.0.
Users are recommended to upgrade to version 1.29.0, which fixes the issue.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
Apache Calcite Avaticato a version that resolves this vulnerability.Fixed in 1.29.0
Event History
Frequently Asked Questions
What must an attacker be able to control to exploit this issue?
An attacker must be able to influence the class name supplied to Avatica plugin-instantiation APIs, such as AvaticaUtils#instantiatePlugin or related methods. Exploitation also depends on a class with a harmful static initializer being present on the application's classpath.
How significant is the practical risk?
The issue is described as low severity because there are currently no well-known or widely used classes with dangerous static initializer blocks. However, affected applications may initialize arbitrary classes named through externally controlled plugin input.
Which deployments are affected and what is the remediation?
Apache Calcite Avatica versions before 1.29.0 are affected. Upgrade to version 1.29.0, which restricts plugin initialization and instantiation to classes implementing the specified plugin interface.