Hey there, Bay Area pals! Today, let’s chat cybersecurity. In particular, I want to dive into a recent piece by Mandiant cybersecurity researchers about a memory-only dropper named PEAKLIGHT. This nasty little bit of malware uses a multistage infection process to deliver what’s called “malware-as-a-service infostealers.” Sounds intense, right? Let’s break it down.
So, what happens first? Let’s imagine an unsuspecting user downloads a suspicious ZIP file that masquerades as a pirated movie. Within these ZIP files, there’s a harmful file that initiates a connection to a URL hosting harmful payloads. These harmful items can be disguised as harmless documents making them tough to spot as a threat.
The PEAKLIGHT infection doesn’t stop there, though. It uses sneaky techniques, like abusing legitimate Content Delivery Networks (CDNs), to deploy malicious software. This helps the malware to bypass security measures as most CDNs have a good reputation.
In PEAKLIGHT’s next phase, a Javascript is delivered that runs an embedded payload and leads to the next step of the PowerShell downloader attack chain. This payload delivers the downloader straight onto the unsuspecting user’s system.
Now we’re onto stage 4. The PEAKLIGHT downloader dutifully delivers and executes the final payload. These payloads take the form of ZIP archives, which are downloaded, of course, from reputable CDNs. Upon execution, the infostealers are installed onto the user’s system. It’s a fable as old as time, folks!
This whole process was analyzed using two different instances of the harmful archive files, designated as K1.zip. These archives were first noticed back in April and May 2024, showing a relatively low detection rate until alarms started ringing on 22 Aug 2024. However, this warning came only a short while before the Mandiant researchers unveiled their PEAKLIGHT findings.
The seemingly successful low-profile existence of these harmful elements from April-August 2024 tells us something useful. Threats like PEAKLIGHT are indeed complex and sophisticated, capable of slipping past even state-of-the-art defenses.
One interesting case we came across involved a global healthcare manufacturing company. One of their locations was specifically targeted, but the campaign was successfully halted before it could deliver harmful infostealers via an AutoIT script.
When we talk about cybersecurity strategies, this case study illustrates the need for a strong “Defense-in-Depth” approach. Threats like the PEAKLIGHT PowerShell downloader demonstrate the sophisticated attacks that cyber crooks are now creating to hoodwink detection measures.
An important measure against these threats is the use of Adaptive Moving Target Defense (AMTD). This approach brings dynamism during the loading of applications in runtime and denies attackers the ideal environment to run their foul plays. The great thing about this is that it doesn’t need previous knowledge of the attack and doesn’t involve a signature – talk about relieving the IT Security team’s burden!
In addition, combining AMTD with the strategy of Adaptive Exposure Management will offer organizations visibility of exposed attack surfaces, creating a more secure anti-Ransomware model.
That’s all for today, folks! Stay safe out there in the digital wilderness, and let’s make sure the Bay Area remains a stronghold against these cyber threats.
by Morgan Phisher | HEAL Security
