Several ransomware groups are exploiting CVE-2026-0257, an authentication bypass in Palo Alto Networks’ PAN-OS GlobalProtect patched in May, to break into organizations in sectors ranging from healthcare and education to government and energy. CVE-2026-0257 stems from the firewalls relying on cookies without performing detailed validation and integrity checking, which allows remote, unauthenticated attackers to bypass security restrictions and establish an unauthorized VPN connection. The vulnerabilities affect the GlobalProtect portal and gateway of PAN’s physical and … More → The post Ransomware gangs have been exploiting Palo Alto GlobalProtect VPN flaw since June appeared first on Help Net Security .

Palo Alto Networks has disclosed that it's continuing to observe exploitation of a now-patched security flaw impacting  PAN-OS and Prisma Access by ransomware actors. The activity relates to CVE-2026-0257 (CVSS score: 7.8), an authentication bypass flaw that could be exploited by bad actors to set up unauthorized VPN connections. It was patched by Palo Alto Networks in May 2026 and was

Qilin ransomware exploits the PAN-OS GlobalProtect flaw CVE-2026-0257 to gain unauthorized VPN access to unpatched networks. Arctic Wolf researchers warn that the Qilin ransomware gang is exploiting the critical PAN-OS GlobalProtect vulnerability CVE-2026-0257 to compromise corporate networks. CVE-2026-0257 is a PAN-OS authentication bypass vulnerability affecting GlobalProtect portals and gateways. Palo Alto Networks addressed the vulnerability on May […]

Threat actors have been observed exploiting a now-patched high-severity Palo Alto Networks PAN-OS vulnerability as an entry point to deploy Qilin (aka Agenda) ransomware on victim environments. Arctic Wolf Labs said it investigated multiple intrusions in June 2026 that began with the exploitation of CVE-2026-0257 (CVSS score: 7.8), an authentication bypass flaw affecting the portal and gateway

Palo Alto Networks warns that attackers are actively exploiting CVE-2026-0257, a PAN-OS flaw that lets unauthorized users bypass authentication and establish VPN connections. Palo Alto Networks has confirmed active exploitation of CVE-2026-0257, a PAN-OS authentication bypass vulnerability affecting GlobalProtect portals and gateways. Palo Alto Networks addressed the vulnerability on May 13. Two weeks later, cybersecurity firm Rapid7 […]

We include indicators of activity and mitigations for PAN-OS vulnerability CVE-2026-0257. The post Threat Brief: Active Exploitation of PAN-OS CVE-2026-0257 appeared first on Unit 42 .