Hi,

I tried installing ActiveMQ 5.16.4 which comes with reload4j-1.2.19, now running the detector shows the following output:

-- github.com/mergebase/log4j-detector v2021.12.29 (by mergebase.com) analyzing paths (could take a while).
-- Note: specify the '--verbose' flag to have every file examined printed to STDERR.
activemq-all-5.16.4.jar contains Log4J-1.x <= 1.2.17 _OLD_

As per raising the issue with the AMQ team, we received the following comment:

The Log4J transitive dependency from Zookeeper related bits were excluded (directly or via dependencyManagement) and reload4j was added to activemq-partition as a dependency to serve in their place during AMQ-8472. The classes included in activemq-all thus should be those from reload4j, which necessarily uses the same org.apache.log4j namespace to serve their intent to act as a substitute for Log4j.

After some inspection, I figured that the log4j-detector jar is doing a check with the same namespace as it is in log4j-1.x hence seeing the issue:

private static final String FILE_OLD_LOG4J = "log4j/DailyRollingFileAppender.".toLowerCase(Locale.ROOT);

Since reload4j has resolved the vulnerability as seen in log4j-1.x but uses the same namespace, I believe the condition check for checking the existence of log4j-1.x shall be improved here or else all reload4j jars will be wrongly detected as vulnerable.