{"id":"CVE-2026-33701","aliases":["GHSA-xw7x-h9fj-p2c7"],"url":"https://o3.security/vulnerability/CVE-2026-33701","summary":"OpenTelemetry: Unsafe Deserialization in RMI Instrumentation may Lead to Remote Code Execution","details":"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.","published":"2026-03-27T00:01:12.327Z","modified":"2026-08-18T13:03:08.213762Z","cvss":null,"epss":{"score":0.00921,"percentile":0.5864,"asOf":"2026-09-17"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Maven","name":"io.opentelemetry.javaagent:opentelemetry-javaagent","fixedVersion":"2.26.1"}],"fix":{"url":"https://github.com/open-telemetry/opentelemetry-java-instrumentation/commit/9cf4fbaaa9e79226142b2ed42a6f6b4ac0be2197","label":"open-telemetry/opentelemetry-java-instrumentation@9cf4fba"},"references":[{"type":"WEB","url":"https://github.com/open-telemetry/opentelemetry-java-instrumentation/releases/tag/v2.26.1"},{"type":"WEB","url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-33701.json"},{"type":"ADVISORY","url":"https://access.redhat.com/security/cve/CVE-2026-33701"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/33xxx/CVE-2026-33701.json"},{"type":"ADVISORY","url":"https://github.com/open-telemetry/opentelemetry-java-instrumentation/security/advisories/GHSA-xw7x-h9fj-p2c7"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-33701"},{"type":"REPORT","url":"https://bugzilla.redhat.com/show_bug.cgi?id=2452071"},{"type":"FIX","url":"https://github.com/open-telemetry/opentelemetry-java-instrumentation/commit/9cf4fbaaa9e79226142b2ed42a6f6b4ac0be2197"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-18T13:03:08.213762Z"}}