Book a Security Review

Known exploited · Apache

CVE-2023-46604: Apache ActiveMQ Deserialization of Untrusted Data Vulnerability

What it is

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.

Added November 2, 2023Due November 23, 2023CISA KEV catalog 2026.10.01

Vendor
Apache
Product
ActiveMQ
Added to KEV
November 2, 2023
CISA due date
November 23, 2023
Ransomware use
Known

What CISA requires

Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

Forensic triage

No

What to do now

  1. Find every instance of ActiveMQ you run, including the forgotten ones, and check its version against the vendor advisory.
  2. Apply the vendor's fix or mitigation, before November 23, 2023 if you are bound by CISA's deadline, sooner if it faces the internet.
  3. Assume it was tried against you already: look for signs of exploitation from the date it was added, not from the day you patched.
  4. Until every instance is patched, block the attack at the edge: a WAF in blocking mode stops Java deserialization payloads.

References

CVE-2023-46604 in the National Vulnerability Database

The Dome

Block it at the edge while you patch

The Dome's WAF runs the OWASP Core Rule Set in blocking mode and stops Java deserialization payloads before they reach your application.

See the Dome

T Academy

Train the engineers who fix it

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Source: CISA Known Exploited Vulnerabilities Catalog (public domain), catalog version 2026.10.01.