IRONSMITHINTEL
CRITICALCVSS10.0
|
Actively Exploited
|CISA KEV|CVE-2023-46604|Auth: none — unauthenticated|Reboot: required|Manual only

Apache ActiveMQ Deserialization of Untrusted Data Vulnerability

Apache ActiveMQ contains a deserialization of untrusted data vulnerability that may allow a remote attacker with network access to a broker to run shell commands by manipulating serialized class types in the OpenWire protocol to cause the broker to instantiate any class on the classpath.

Published Oct 27, 2023 · Updated May 16, 2026
Why patchRisk explained in plain English
Worst-case scenarioIf unpatched

A remote attacker, without authentication, can achieve partial data exposure, arbitrary modification of data, complete denial of service or system unavailability. CISA has confirmed use of this vulnerability in known ransomware campaigns — treat as high priority for remediation. Federal agencies are required to remediate by 2023-11-23 under CISA BOD 22-01.

How the attack worksNo clicks needed

This is a Deserialization of Untrusted Data (CWE-502) vulnerability in Apache ActiveMQ. The Java OpenWire protocol marshaller is vulnerable to Remote Code Execution. This vulnerability may allow a remote attacker with network access to either a Java-based OpenWire broker or client to run arbitrary shell commands by manipulating serialized class types in the OpenWire protocol to cause either the client or the broker (respectively) to instantiate any class on the classpath. Users are recommended to upgrade both brokers and clients to version 5.15.16, 5.16.7, 5.17.6, or 5.18.3 which fixes this issue. Exploitation requires remote network access, low attack complexity, no authentication required, and no user interaction required.

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Phishing link

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Malicious file

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Server compromised

Am I affected?Quick check

Probably yes if any of these apply:

●IT Security
●Running activemq: v < 5.15.16, 5.16.0 ≤ v < 5.16.7, 5.17.0 ≤ v < 5.17.6, 5.18.0 ≤ v < 5.18.3; activemq legacy openwire module: v < 5.15.16, 5.16.0 ≤ v < 5.16.7, 5.17.0 ≤ v < 5.17.6, 5.18.0 ≤ v < 5.18.3; debian linux: 10.0, 11.0; e-series santricity unified manager: -; e-series santricity web services proxy: -; santricity storage plugin: -
Real-world incidentsWhat we've seen

Used in known ransomware campaigns. Threat-research write-up: https://packetstormsecurity.com/files/175676/Apache-ActiveMQ-Unauthenticated-Remote-Code-Execution.html

How to patch

Manual remediation steps

Apply the Vendor Patch

This vulnerability is in the CISA Known Exploited Vulnerabilities catalog — apply the vendor's security update as soon as possible.

CISA required action: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

References

    1
    Vendor advisory: https://activemq.apache.org/security-advisories.data/CVE-2023-46604-announcement.txt
    1
    NVD entry: https://nvd.nist.gov/vuln/detail/CVE-2023-46604
    1
    CISA KEV: https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-46604
PowerShell automationComing soon

No tested PowerShell script for this entry yet. We’re prioritising automation based on user demand.

References

↗ CVE-2023-46604↗ NVD↗ Vendor Advisory