GHSA-h8w2-rv57-vc6f splunk-otel-javaagent: Unsafe deserialization in RMI instrumentation may lead to Remote Code Execution
Unsafe deserialization in Splunk OpenTelemetry Java agent allows remote code execution if RMI is exposed and gadget chains exist.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is GHSA-h8w2-rv57-vc6f?
GHSA-h8w2-rv57-vc6f is an unsafe deserialization vulnerability in com.splunk:splunk-otel-javaagent, published on 26 Mar 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
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:
- Splunk Distribution of OpenTelemetry Java is attached as a Java agent (
-javaagent) - An RMI endpoint is network-reachable (e.g. JMX remote port, an RMI registry, or any application-exported RMI service)
- 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
References
Which versions are affected by GHSA-h8w2-rv57-vc6f?
2 open source packages ship an affected version, including com.splunk:splunk-otel-javaagent.
| Package | Affected | Fixed in |
|---|---|---|
com.splunk:splunk-otel-javaagent Maven | All versions | 2.26.1 |
com.splunk:splunk-otel-javaagent Maven | All versions | 2.26.1 |
How do I fix GHSA-h8w2-rv57-vc6f?
Upgrade com.splunk:splunk-otel-javaagent to 2.26.1 or later.
Upgrade, and only deserialise data from trusted sources or with an allow-list of types. More about Unsafe deserialization.
Is GHSA-h8w2-rv57-vc6f being exploited?
There is no known exploitation of GHSA-h8w2-rv57-vc6f in the wild and no public exploit code.