CVE-2026-33701
OpenTelemetry: Unsafe Deserialization in RMI Instrumentation may Lead to Remote Code Execution
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
OpenTelemetry: Unsafe Deserialization in RMI Instrumentation may Lead to Remote Code Execution
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.
- Record
CVE-2026-33701- CVSS 4.0
- 9.3 Critical
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - CVSS 3.1
- 8.1 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-502, CWE-502
- Updated
- 2026-11-02
EUVDEUVD-2026-16498
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.
- Record
EUVD-2026-16498- CVSS 4.0
- 9.3 Critical
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-xw7x-h9fj-p2c7
OpenTelemetry: Unsafe Deserialization in RMI Instrumentation may Lead to Remote Code Execution
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:
- OpenTelemetry Java instrumentation 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
Credits
This vulnerability was responsibly disclosed in coordination with Datadog.
- Record
GHSA-xw7x-h9fj-p2c7- CVSS 4.0
- 9.3 Critical
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-502
- Updated
- 2026-11-02
NVD
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.
- Record
CVE-2026-33701- CVSS 4.0
- 9.3 Critical
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - CVSS 3.1
- 8.1 High
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-502
- Updated
- 2026-11-02
OSV
OpenTelemetry: Unsafe Deserialization in RMI Instrumentation may Lead to Remote Code Execution
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.
- Record
CVE-2026-33701- CVSS 4.0
- 9.3 Critical
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - Weakness
- CWE-502
- Updated
- 2026-11-02
OSVGHSA-xw7x-h9fj-p2c7
OpenTelemetry: Unsafe Deserialization in RMI Instrumentation may Lead to Remote Code Execution
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:
- OpenTelemetry Java instrumentation 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
Credits
This vulnerability was responsibly disclosed in coordination with Datadog.
- Record
GHSA-xw7x-h9fj-p2c7- CVSS 4.0
- 9.3 Critical
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-502
- Updated
- 2026-11-02
OSVROOT-APP-MAVEN-CVE-2026-33701 No score
CVE-2026-33701 in io.opentelemetry.javaagent:opentelemetry-javaagent - Patched by Root
Root has patched CVE-2026-33701 in the io.opentelemetry.javaagent:opentelemetry-javaagent package for Root:Maven. Multiple fixed versions available.
- Record
ROOT-APP-MAVEN-CVE-2026-33701- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
io.opentelemetry.javaagent:opentelemetry-javaagentMaven |
before 2.26.1 | 2.26.1 |
io.opentelemetry.javaagent:opentelemetry-javaagentMaven |
before 2.26.1, plus listed versions 0.12.00.12.10.13.00.13.10.14.0 Show 45 moreShow less0.15.00.15.10.16.00.16.10.17.01.0.01.0.11.1.01.10.01.10.11.11.01.11.11.12.01.12.11.13.01.13.11.14.01.15.01.16.01.17.01.18.01.19.01.19.11.19.21.2.01.20.01.20.11.20.21.21.01.22.01.22.11.23.01.24.01.25.01.25.11.26.01.27.01.28.01.29.01.3.01.3.11.30.01.31.01.32.01.32.1 |
2.26.1 |
io.opentelemetry.javaagent:opentelemetry-javaagentRoot:Maven |
before 2.10.0-aikido.2 | 2.10.0-aikido.22.10.0-aikido.32.10.0-aikido.1 |
io.root.io.opentelemetry.javaagent:opentelemetry-javaagentRoot:Maven |
before 2.10.0-root.io.2 | 2.10.0-root.io.22.10.0-root.io.32.10.0-root.io.1 |
Public exploits
Links only. Every CVE stores no exploit code.
| Source | Link | Date |
|---|---|---|
| PoC in GitHub | pl4tyz/CVE-2026-33701-Unsafe-Deserialization-in-OpenTelemetry-Java-Agent-RMI-Instrumentation | 2026-04-04 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV, PoC in GitHub |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-33701 is a critical vulnerability (CVSS 9.3) in Linuxfoundation Opentelemetry Instrumentation For Java, published March 25, 2026. Public exploit code exists. EPSS puts the chance of exploitation in the next 30 days at 0.94%, the 60th percentile. Fixed in io.opentelemetry.javaagent:opentelemetry-javaagent 2.26.1.
References
github.com/open-telemetry/opentelemetry-java-instrumentation/security/advisories/GHSA-xw7x-h9fj-p2c7
access.redhat.com/security/cve/CVE-2026-33701
bugzilla.redhat.com/show_bug.cgi?id=2452071
security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-33701.json
Left out here: 56 versions. The JSON record has them.