CVE-2026-18061 - XML External Entity (XXE) in AWS Advanced JDBC Wrapper RemoteQueryCachePlugin

CVE-2026-18061 - XML External Entity (XXE) in AWS Advanced JDBC Wrapper RemoteQueryCachePlugin

Bulletin ID: 2026-109-AWS
Scope: AWS
Content Type: Important (requires attention)
Publication Date: 09/11/2026 09:30 AM PDT

The AWS Advanced JDBC Wrapper is an open-source library that enhances existing JDBC drivers with AWS-specific capabilities such as Aurora failover, IAM authentication, and automated SQL query caching for applications connecting to Amazon Aurora, RDS MySQL, and RDS MariaDB.

We identified CVE-2026-18061, an improper restriction of XML external entity (XXE) references in the optional RemoteQueryCachePlugin. When this plugin is enabled with a shared cache, an actor with write access to that cache infrastructure might place crafted XML in a cached column value. When an application subsequently reads that cached result as XML, the wrapper's XML parsers resolve external entities, which might allow the actor to disclose sensitive files readable by the application process, including stored database and IAM role credentials.

Impacted versions: >= 3.3.0 and <= 4.2.0

This issue has been addressed in AWS Advanced JDBC Wrapper version 4.3.0. We recommend upgrading to the latest version and ensuring any forked or derivative code is patched to incorporate the new fixes.

The RemoteQueryCachePlugin is not enabled by default. Customers who cannot immediately upgrade can mitigate this issue by not enabling the RemoteQueryCachePlugin, or by restricting write access to the shared cache so that only trusted principals can write to it.