A recent proof-of-concept (PoC) exploit for a vital safety vulnerability in Apache ActiveMQ is making it simpler than ever to realize distant code execution (RCE) on servers working the open supply message dealer — avoiding discover whereas doing so.
The max-severity bug (CVE-2023-46604, CVSS rating of 10) permits unauthenticated menace actors to run arbitrary shell instructions, and it was patched by Apache late final month. Nonetheless, hundreds of organizations stay susceptible, a state of affairs that the HelloKitty ransomware gang and others have taken full benefit of.
Whereas assaults have thus far relied on a public PoC launched shortly after the flaw’s disclosure, researchers at VulnCheck stated this week that they’ve engineered a extra elegant exploit — one which cuts down on intruder noise by launching assaults from reminiscence.
“Which means the menace actors might have averted dropping their instruments to disk,” in response to VulnCheck’s submit detailing the brand new ActiveMQ exploit. “They may have simply written their encryptor in Nashorn (or loaded a category/JAR into reminiscence) and remained memory-resident, maybe avoiding detection from … managed [endpoint detection and response] EDR groups.”
New ActiveMQ Exploit: Enabling a Silent Stalker
Whereas attackers would want to delete any incriminating log messages within the activemq.log to totally cowl their tracks, the VulnCheck PoC continues to be a big enchancment in relation to making any assaults in opposition to the vulnerability stealthier, in response to Matt Kiely, principal safety researcher at Huntress.
“The proof of idea from VulnCheck is a marked evolution from the earlier public PoCs, which usually relied on utilizing the shell of the exploited system to execute code,” he says, including that the Huntress staff confirmed that the brand new method certainly works as marketed.
Additional, “this particular assault is trivial to take advantage of if an attacker can entry the susceptible occasion of ActiveMQ,” he says, including that extra evolutions and enhancements in exploit growth are certain to come back.
Thus, admins needs to be patching CVE-2023-46604 instantly, or eradicating the servers from the Web. It is also necessary to remember that the danger from an assault stretches properly past ransomware, Kiely provides.
“Potential outcomes of exploitation [include] methods like account entry removing, knowledge destruction, defacement, useful resource hijacking, and plenty of others,” he explains. “Attackers might even elect to do nothing in any respect and easily wait on an exploited server to stage additional assaults” — one thing, it needs to be famous, that the silent VulnCheck PoC can extra simply allow.
