Cybersecurity researchers at Unit 42 have uncovered a sophisticated new phishing technique that leverages HTTP response headers to deliver malicious webpages. This technique poses a significant threat to users, as it allows attackers to bypass traditional phishing defenses.
How it Works:
Unlike conventional phishing attacks that inject malicious content into the HTML body, this technique leverages the refresh entry within the HTTP response header. This entry enables attackers to automatically redirect victims to a phishing page without any user interaction. The malicious links often contain the victim’s email address embedded in the refresh field of the HTTP header, allowing for dynamic personalization of the phishing attempt.
Evasion Tactics:
To avoid detection, attackers camouflage the original and landing URLs by hosting them on legitimate or compromised domains. They also employ URL shortening, tracking, and marketing services to further obscure their malicious intent. This makes it more challenging to identify malicious indicators in the URL.
Targeted Industries:
Unit 42’s research revealed that these phishing campaigns primarily target large corporations in South Korea, government agencies, and schools in the United States. Affected industries include Business and Economy, Financial Services, Government, Health and Medicine, and Computer and Internet.
Impersonation Targets:
Attackers frequently impersonate popular services such as Microsoft Outlook webmail login pages. These phishing pages are pre-filled with the victim’s email address and are designed to capture their password.
Protection Measures:
To protect against these advanced phishing attacks, Palo Alto Networks recommends:
- Deploying Advanced URL Filtering (AURL) to identify phishing URLs and analyze suspicious patterns
- Educating users about the dangers of clicking on email links, especially those requesting login credentials
- Implementing multi-factor authentication (MFA) to prevent unauthorized access even in the event of compromised credentials
Conclusion:
This novel phishing technique using HTTP response headers is a serious threat that requires immediate attention. By staying informed about the latest attack methodologies, organizations and individuals can take proactive measures to protect themselves and their data from these sophisticated phishing attempts.
