In versions prior to 2.26.1, the RMI instrumentation registered a custom endpoint that deserialized incoming data without applying serialization filters. An attacker with network access to a JMX or RMI port on an instrumented JVM could exploit this to potentially achieve remote code execution. All three of the following conditions must be true to exploit this vulnerability: 1. OpenTelemetry Java instrumentation is attached as a Java agent (-javaagent) 2. An RMI endpoint is network-reachable (e.g. JMX remote port, an RMI registry, or any application-exported RMI service) 3. A gadget-chain-compatible library is present on the classpath

Impact Arbitrary remote code execution with the privileges of the user running the instrumented JVM.

Recommendation Upgrade to version 2.26.1 or later.

Workarounds Set the following system property to disable the RMI integration:

-Dotel.instrumentation.rmi.enabled=false

Credits This vulnerability was responsibly disclosed in coordination with Datadog.

OpenTelemetry Java Instrumentation JDBC auto-instrumentation may fail to sanitize passwords in SQL CONNECT statements when the password is double-quoted. As a result, clear-text database passwords can be added to trace span attributes and exported to observability backends.

OpenTelemetry Java Instrumentation provides OpenTelemetry auto-instrumentation and instrumentation libraries for Java. In versions prior to 2.27.0, the RMI context propagation payload reader limits the number of context entries but does not limit the aggregate size of the strings read from the stream. An attacker who can reach an RMI endpoint on an instrumented JVM can send an oversized context propagation payload. This can cause excessive memory allocation while the JVM reads the payload, potentially leading to denial of service. The issue affects only deployments where RMI instrumentation is enabled and an RMI endpoint is network-reachable. This issue has been fixed in version 2.27.0.