Saturday, July 20, 2024
EHA

Hackers Using Weaponized PDF Files to Deliver Qakbot Malware

Qakbot is a sophisticated banking trojan and malware that primarily targets financial institutions. This sophisticated malware steals sensitive information such as:-

  • Login credentials
  • Financial data

While hackers exploit Qakbot to conduct:-

  • Financial fraud
  • Unauthorized transactions
  • Gain access to personal data
  • Gain access to financial information

Qakbot malware returns after the “Duck Hunt” bust. Not only that, even Microsoft has found small-scale phishing targeting the hospitality sector since Dec 11, 2023.

Microsoft discovery of Qakbot resurface (Source - K7)
Microsoft discovery of Qakbot resurface (Source – K7)

Though all these phishing emails are low now, researchers at K7 Security Labs affirmed to expect an email volume surge due to Qakbot’s history.

Cybersecurity researchers at K7 Security Labs recently discovered that hackers use weaponized PDF files to deliver Quakbot malware.

Document
Free Webinar

Fastrack Compliance: The Path to ZERO-Vulnerability

Compounding the problem are zero-day vulnerabilities like the MOVEit SQLi, Zimbra XSS, and 300+ such vulnerabilities that get discovered each month. Delays in fixing these vulnerabilities lead to compliance issues, these delay can be minimized with a unique feature on AppTrana that helps you to get “Zero vulnerability report” within 72 hours.

PDF Files to Deliver Qakbot Malware

In a recent phishing campaign, researchers identified threat actors actively delivering malicious MSI files via PDFs. Further, the analysis uncovers a patched IDM DLL housing Qakbot, which is found to be using a custom packer. 

Besides this, unpacking the Qakbot DLL involves breakpoints on:-

  • VirtualAlloc()
  • VirtualProtect()

Initially, experts obtained the dump without the MZ header, and later, they identified it as Qakbot’s second-stage loader by adding the header manually. This technique helps the threat actors avoid EDR detection by avoiding MZ header scans.

Execution Flow (Source - K7)
Execution Flow (Source – K7)

In the new Qakbot campaign, security researchers noted AES encryption for victim info storage, yet the final payload retains RC4 encryption. The dynamic analysis discreetly exposes an MSI-installed temp file invoking rundll32.exe. 

The threat actor leveraging the PDFs self-copies the DLL as AcrobatAC.dll and then executes the Qakbot via EditOwnerInfo. 

The malicious DLL suspends the wermgr.exe (Windows Error Manager) as part of the kill chain. Besides this, the experts also extracted the Qakbot payload by dumping the PE file from the suspended wermgr.exe, which reveals the use of process hollowing.

Qakbot pretends to be wermgr.exe and tries to establish a covert C2 connection, however, the C2 which is inactive during analysis stops the further malicious actions.

IoCs

IoCs (Source - K7)
IoCs (Source – K7)

Looking for cost-effective penetration testing services? Try Kelltron’s to assess and evaluate the security posture of digital systems –

Website

Latest articles

Hackers Claiming Dettol Data Breach: 453,646 users Impacted

A significant data breach has been reported by a threat actor known as 'Hana,'...

CrowdStrike Update Triggers Widespread Windows BSOD Crashes

A recent update from cybersecurity firm CrowdStrike has caused significant disruptions for Windows users,...

Operation Spincaster Disrupts Approval Phishing Technique that Drains Victim’s Wallets

Chainalysis has launched Operation Spincaster, an initiative to disrupt approval phishing scams that have...

Octo Tempest Know for Attacking VMWare ESXi Servers Added RansomHub & Qilin to Its Arsenal

Threat actors often attack VMware ESXi servers since they accommodate many virtual machines, which...

TAG-100 Actors Using Open-Source Tools To Attack Gov & Private Orgs

Hackers exploit open-source tools to execute attacks because they are readily available, well-documented, and...

macOS Users Beware Of Weaponized Meeting App From North Korean Hackers

Meeting apps are often targeted and turned into weapons by hackers as they are...

Hackers Exploiting Legitimate RMM Tools With BugSleep Malware

Since October 2023, MuddyWater, which is an Iranian threat group linked to MOIS, has...
Tushar Subhra Dutta
Tushar Subhra Dutta
Tushar is a Cyber security content editor with a passion for creating captivating and informative content. With years of experience under his belt in Cyber Security, he is covering Cyber Security News, technology and other news.

Free Webinar

Low Rate DDoS Attack

9 of 10 sites on the AppTrana network have faced a DDoS attack in the last 30 days.
Some DDoS attacks could readily be blocked by rate-limiting, IP reputation checks and other basic mitigation methods.
More than 50% of the DDoS attacks are employing botnets to send slow DDoS attacks where millions of IPs are being employed to send one or two requests per minute..
Key takeaways include:

  • The mechanics of a low-DDoS attack
  • Fundamentals of behavioural AI and rate-limiting
  • Surgical mitigation actions to minimize false positives
  • Role of managed services in DDoS monitoring

Related Articles