@LaJoieSecurity Threat Blog

How Corrupted Word Docs and QR Codes Are Outsmarting Traditional Security

TLDR: 

 

 

 

 

In a recent wave of sophisticated cyberattacks, threat actors employ corrupted Microsoft Word documents in phishing campaigns to bypass security measures and harvest user credentials. This method exploits Microsoft Word's file recovery feature, presenting a novel challenge to traditional security protocols.

 

Attack Methodology (a feature not a bug!):

Corrupted Document Delivery: Attackers distribute emails with intentionally corrupted Word attachments, often disguised as communications from payroll or human resources departments. These emails lure recipients with subjects related to employee benefits or bonuses.

 

Exploitation of Recovery Feature: When the recipient attempts to open the corrupted document, Microsoft Word's recovery mode activates, reconstructing the file. The recovered document typically displays a message prompting the user to scan a QR code to view the full content.

 

QR Code Credential Harvesting: Scanning the QR code directs users to a counterfeit Microsoft login page designed to steal their credentials. This tactic effectively shifts the attack vector from the user's computer to their mobile device, which may lack robust security controls.

 

Defense Evasion Tactics:

By utilizing corrupted documents, attackers can evade detection by security software that may not thoroughly scan or analyze damaged files. The incorporation of QR codes further complicates detection, as traditional email security solutions often do not scrutinize image-based content.

 

Recent Incidents:

In August 2023, a significant phishing campaign targeted various industries by embedding malicious QR codes in emails, aiming to steal Microsoft credentials. Notably, a major U.S. energy company was among the affected organizations.

 

Mitigation Strategies:

  • User Education: Train employees to recognize phishing attempts, especially those involving unexpected attachments or QR codes.
  • Enhanced Security Measures: Implement email filtering solutions capable of analyzing and detecting malicious content within attachments and images.
  • Mobile Device Security: Ensure that mobile devices used to scan QR codes are equipped with security software to detect and block malicious sites.

 

As cyber threats continue to evolve, staying informed about emerging tactics is crucial for maintaining robust security postures.

 

Read More

  • Bleeping Computer. (2024, December 10). Novel Phishing Campaign Uses Corrupted Word Documents to Evade Security.  bleepingcomputer.com

  • Infosecurity Magazine. (2024, December 8). Corrupted Word Files Fuel Phishing Attacks. infosecurity-magazine.com

  • Microsoft Tech Community. (2024, December 6). Hunting for QR Code AiTM Phishing and User Compromise. techcommunity.microsoft.com

  • Barracuda Blog. (2024, October 22). Threat Spotlight: Evolving QR Code Phishing Attacks. blog.barracuda.com

  • Cyber Security News. (2023, August 25). Attackers Weaponizing QR Codes for Phishing Campaigns. cybersecuritynews.com