Vulnerability Description
OpenTelemetry Java Instrumentation provides OpenTelemetry auto-instrumentation and instrumentation libraries for Java. In versions prior to 2.26.1, the RMI instrumentation registered a custom endpoint that deserialized incoming data without applying serialization filters. On JDK version 16 and earlier, 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: First, OpenTelemetry Java instrumentation is attached as a Java agent (`-javaagent`) on Java 16 or earlier. Second, JMX/RMI port has been explicitly configured via `-Dcom.sun.management.jmxremote.port` and is network-reachable. Third, gadget-chain-compatible library is present on the classpath. This results in arbitrary remote code execution with the privileges of the user running the instrumented JVM. For JDK >= 17, no action is required, but upgrading is strongly encouraged. For JDK < 17, upgrade to version 2.26.1 or later. As a workaround, set the system property `-Dotel.instrumentation.rmi.enabled=false` to disable the RMI integration.
CVSS Score
CRITICAL
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Linuxfoundation | Opentelemetry Instrumentation For Java | < 2.26.1 |
Related Weaknesses (CWE)
References
- https://github.com/open-telemetry/opentelemetry-java-instrumentation/commit/9cf4Patch
- https://github.com/open-telemetry/opentelemetry-java-instrumentation/releases/taRelease Notes
- https://github.com/open-telemetry/opentelemetry-java-instrumentation/security/adMitigationVendor Advisory
FAQ
What is CVE-2026-33701?
CVE-2026-33701 is a vulnerability with a CVSS score of 9.8 (CRITICAL). OpenTelemetry Java Instrumentation provides OpenTelemetry auto-instrumentation and instrumentation libraries for Java. In versions prior to 2.26.1, the RMI instrumentation registered a custom endpoint...
How severe is CVE-2026-33701?
CVE-2026-33701 has been rated CRITICAL with a CVSS base score of 9.8/10. This is considered a critical vulnerability requiring immediate attention.
Is there a patch for CVE-2026-33701?
Check the references section above for vendor advisories and patch information. Affected products include: Linuxfoundation Opentelemetry Instrumentation For Java.