Qilin Ransomware Exploits Palo Alto VPN Bypass
Ransomware operators are still exploiting a patched Palo Alto Networks VPN flaw to break into corporate networks, according to an updated investigation by the company's Unit 42 threat-intelligence team. The flaw, CVE-2026-0257, is an authentication bypass in PAN-OS GlobalProtect that can allow an attacker to establish an unauthorised VPN session, including bypassing multi-factor authentication controls.
From VPN access to domain credentials
Unit 42's 19 October update names two ransomware operators exploiting the flaw: Spikey Scorpius, also known as Qilin, and Tarnished Scorpius, also known as INC. The flaw was patched by Palo Alto Networks in May 2026 and added to the US CISA Known Exploited Vulnerabilities catalogue in May 2026. Unit 42 says its investigations have continued since early June and span sectors including education, financial services, healthcare, manufacturing, government and utilities. Once inside, the attackers typically conduct internal reconnaissance using dual-use remote monitoring tools, move laterally through RDP and SMB, and stage tooling for credential harvesting, data theft and ransomware deployment. Unit 42 highlights a newer and more serious evolution: in one case, attackers moved from the compromised VPN gateway to the vCenter management appliance, disabled security controls on ESXi hypervisors, and used a custom tool to dump credentials offline from a domain controller's virtual disk.
Why unpatched gateways remain dangerous
That technique matters because it can bypass endpoint detection running inside the virtual machine itself. The lesson is not only to patch GlobalProtect, but to check whether authentication override cookies are enabled and whether gateway configurations expose the keys needed to forge them. Palo Alto Networks rates the flaw at CVSS 7.8. No total number of confirmed compromised organisations has been published, so this story makes no claim about victim counts. Organisations running vulnerable GlobalProtect portals or gateways should treat them as exposed until patched and reviewed.
