OpenDJ Pre-Auth RCE via Java Deserialization in JMX RMI

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS 4.0

9.2 · CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N · score source

EPSS

• CVE-2026-46495: 1.13% estimated exploitation activity in the next 30 days; percentile 66.48 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary Description A Deserialization of Untrusted Data (CWE-502) issue in OpenDJ's JMX RMI connector allows an unauthenticated remote attacker to deserialize arbitrary Java objects on the server. The vulnerability exists because the platform reads and processes attacker-controlled bytes prior to authentication. This affects OpenDJ Community Edition through 5.1.0. This has been patched in version 5.1.1. Impact This impacts all current OpenDJ releases where the JMX Connection Handler is enabled. While disabled by default, it is frequently enabled in practice for monitoring integrations. Exploitation requires TCP reachability to the configured listener and does not require authentication, prior privileges, or client certificates. Successful exploitation results in unauthenticated Remote Code Execution (RCE), with the severity depending on the runtime classpath and Java version. Unauthenticated RCE was demonstrated on the OpenDJ 4.4.15 (JDK 11 + Jackson 2.12.6.1). Patch This has been…

Published by the source

22 Jun 2026, 21:10 UTC

Last modified by the source

22 Jun 2026, 21:10 UTC

Source last checked

26 Oct 2026, 16:53 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-43x2-g84q-fmqx

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# Patch Next advisory brief: CVE-2026-46495

Advisory: OpenDJ Pre-Auth RCE via Java Deserialization in JMX RMI
IDs: CVE-2026-46495, GHSA-43x2-g84q-fmqx
Record: https://patchnext.com/advisories/cve-2026-46495 (revision 1, source checked 26 Oct 2026, 16:53 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Critical (CVSS 9.2)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: org.openidentityplatform.opendj:opendj-server-legacy 5.1.1. A vendor fix does not mean a deployment is fixed.

## Affected components
- Maven org.openidentityplatform.opendj:opendj-server-legacy: affected <= 5.1.0; fixed in 5.1.1

## Suggested inspection (read-only)
- Maven org.openidentityplatform.opendj:opendj-server-legacy: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on org.openidentityplatform.opendj:opendj-server-legacy.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-43x2-g84q-fmqx (GitHub-reviewed advisory GHSA-43x2-g84q-fmqx lists affected ranges: Maven org.openidentityplatform.opendj:opendj-server-legacy >=0 <=5.1.0)

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