# 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.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 26 Mar 2026

## 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:
1. Splunk Distribution of OpenTelemetry Java 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
```

### References
[Advisory in OpenTelemetry Instrumentation for Java](https://github.com/open-telemetry/opentelemetry-java-instrumentation/security/advisories/GHSA-xw7x-h9fj-p2c7)

## Which versions are affected by GHSA-h8w2-rv57-vc6f?

2 open source packages ship an affected version, including com.splunk:splunk-otel-javaagent.


| Package | Ecosystem | 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.

## 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.

## Fix prompt for AI coding agents

```text
Check this codebase for GHSA-h8w2-rv57-vc6f and fix it if it is affected.

What it is: 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.
Exploitation: There is no known exploitation of GHSA-h8w2-rv57-vc6f in the wild and no public exploit code.

Affected packages and fixed versions:
- com.splunk:splunk-otel-javaagent (Maven): affected all versions; fixed in 2.26.1
- com.splunk:splunk-otel-javaagent (Maven): affected all versions; fixed in 2.26.1

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/GHSA-h8w2-rv57-vc6f/ (Markdown: https://insights.sbomify.com/GHSA-h8w2-rv57-vc6f/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/GHSA-h8w2-rv57-vc6f

---
From sbomify Insights: https://insights.sbomify.com/GHSA-h8w2-rv57-vc6f/
Summaries are generated and may contain mistakes; the official description above is the record.