Zero-Day PDF Vulnerability Puts Windows NTLM Data at Risk
Security researchers have discovered a zero-day vulnerability in Adobe Acrobat Reader and Foxit Reader that exposes sensitive NTLM (NT LAN Manager) authentication data. This serious flaw can allow cybercriminals to exploit malicious PDF files to steal Windows credentials and gain unauthorized access to networks.
How the Attack Works
Hackers craft malicious PDF files that, when opened, trigger automatic network requests. These requests leak NTLM hashed credentials to remote servers, enabling attackers to launch relay attacks or brute-force the credentials for full access.
Learn more on Microsoft’s Security Blog.
Detailed insights at Cybersecurity News.
Who Is at Risk?
- Windows Users: Systems using NTLM authentication are the most vulnerable.
- Businesses: Enterprises with PDF workflows are at high risk.
- Remote Teams: VPN users are more exposed to such network threats.
Consequences of the Exploit
- Credential Theft: Hackers can steal NTLM credentials.
- Network Access: Gained credentials allow deeper system access.
- Data Breaches: Sensitive files and systems may be compromised.
How to Stay Protected
- Disable External Content in PDF Readers: Prevent automatic URL access.
- Upgrade Authentication: Move away from NTLM to stronger protocols.
- Patch Software: Regularly update PDF readers for security patches.
- Monitor Network Traffic: Detect and block suspicious activity.
- Employee Training: Educate staff about phishing PDFs.
Adobe and Foxit’s Response
Both companies are working on patches to address the flaw. Users should enable automatic updates and stay alert for security advisories.