{"id":"CVE-2026-33701","title":"OpenTelemetry Java Instrumentation provides OpenTelemetry auto-instrumentation and instrumentation libraries for Java","summary":"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 with…","severity":"critical","cvss":9.8,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","cwe":["CWE-502","CWE-502"],"vendor":"linuxfoundation","product":"opentelemetry_instrumentation_for_java","affected":["opentelemetry_instrumentation_for_java < 2.26.1"],"patched":["opentelemetry_instrumentation_for_java 2.26.1"],"published":"2026-03-27","updated":"2026-08-04","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-33701","references":[{"url":"https://github.com/open-telemetry/opentelemetry-java-instrumentation/commit/9cf4fbaaa9e79226142b2ed42a6f6b4ac0be2197","label":"security-advisories@github.com"},{"url":"https://github.com/open-telemetry/opentelemetry-java-instrumentation/releases/tag/v2.26.1","label":"security-advisories@github.com"},{"url":"https://github.com/open-telemetry/opentelemetry-java-instrumentation/security/advisories/GHSA-xw7x-h9fj-p2c7","label":"security-advisories@github.com"},{"url":"https://access.redhat.com/security/cve/CVE-2026-33701","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2452071","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-33701.json","label":"0b0ca135-0b70-47e7-9f44-1890c2a1c46c"}],"tags":["nvd","exploit-available"],"epss":0.00921,"epssPercentile":0.58268,"ingestedAt":"2026-08-05T11:47:24.304Z","exploits":{"github":1,"githubRepos":["https://github.com/pl4tyz/CVE-2026-33701-Unsafe-Deserialization-in-OpenTelemetry-Java-Agent-RMI-Instrumentation"],"checkedAt":"2026-09-21T15:28:42.476Z"},"exploitAvailable":true,"slug":"CVE-2026-33701","body":"## Overview\n\nOpenTelemetry 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.\n\n## Affected\n\n- `opentelemetry_instrumentation_for_java < 2.26.1`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `opentelemetry_instrumentation_for_java 2.26.1`","depth":"abyssal","depthScore":66,"depthScoreParts":{"impact":53.9,"likelihood":0.2,"exploitation":12,"ransomware":0},"changes":[{"seq":5111,"id":"CVE-2026-33701","ts":1788887248697,"field":"exploit_available","old":"false","new":"true"},{"seq":3994,"id":"CVE-2026-33701","ts":1788886364363,"field":"exploit_available","old":"true","new":"false"},{"seq":2809,"id":"CVE-2026-33701","ts":1788883031073,"field":"exploit_available","old":"false","new":"true"},{"seq":1838,"id":"CVE-2026-33701","ts":1788882433991,"field":"exploit_available","old":"true","new":"false"},{"seq":936,"id":"CVE-2026-33701","ts":1788881868008,"field":"exploit_available","old":"false","new":"true"}]}