Pierluigi Paganini
April 02, 2025
Researchers at the threat intelligence firm GreyNoise warn of hackers that are scanning for vulnerabilities in Palo Alto Networks GlobalProtect portals, likely preparing for targeted attacks, warns threat intelligence firm GreyNoise.
GreyNoise reports that over 24,000 unique IP addresses have attempted to access GlobalProtect portals, indicating a coordinated effort to identify vulnerabilities. From March 17 to 26, activity surged with nearly 20,000 IPs scanning logins daily. GreyNoise identified around 23,000 suspicious IPs and 150 known malicious ones, suggesting a potential targeted attack.
“GreyNoise has observed a significant surge in login scanning activity targeting Palo Alto Networks PAN-OS GlobalProtect portals. Over the last 30 days, nearly 24,000 unique IP addresses have attempted to access these portals.” reads the report published by GreyNoise. “The pattern suggests a coordinated effort to probe network defenses and identify exposed or vulnerable systems, potentially as a precursor to targeted exploitation.”
The experts believe that this activity is part of a reconnaissance effort to test network defenses, potentially paving the way for future attacks. GreyNoise recommends that organizations using Palo Alto Networks products should take steps to secure their login portals.
A large portion of traffic is linked to 3xK Tech GmbH (20,010 IPs) under ASN200373, with contributions from PureVoltage Hosting Inc., Fast Servers Pty Ltd., and Oy Crea Nova Hosting. GreyNoise identified three JA4h hashes related to a login scanner tool. The activity originates mainly from the U.S. (16,249 IPs) and Canada (5,823 IPs), targeting primarily the U.S. (23,768), followed by the U.K., Ireland, Russia, and Singapore.
The researchers also observed scans that are targeting GlobalProtect portals and other PAN-OS appliances like PAN-OS Crawler, similar to threats identified by Cisco Talos in April last year, which targeted Cisco appliances, Microsoft Exchange servers, and edge devices from various vendors.
“Given the unusual nature of this activity, organizations with exposed Palo Alto Networks systems should review their March logs and consider performing a detailed threat hunt on running systems to identify any signs of compromise.” GreyNoise concludes.
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(SecurityAffairs – hacking, GreyNoise)
