Palo Alto PAN-OS Buffer Overflow Lets Attackers Execute Arbitrary Code as Root
Palo Alto Networks fixed CVE-2026-0310, a CVSS 9.2 unauthenticated PAN-OS buffer overflow enabling root code execution on PA-Series firewalls.
Palo Alto Networks published an advisory on September 9, 2026 for CVE-2026-0310, a CWE-787 out-of-bounds write in PAN-OS XML processing with a CVSS v4.0 base score of 9.2, affecting the management and dataplane interfaces. Unauthenticated attackers could execute arbitrary code as root on PA-Series hardware firewalls, while VM-Series faces denial-of-service impact and Prisma Access and Cloud NGFW have reduced, authenticated exposure. Affected releases include PAN-OS 10.2, 11.1, 11.2, 12.1, and 12.2 before fixed maintenance releases such as 12.2.3, 12.1.4-h10, 11.2.13-h2, 11.1.16-h2, and 10.2.18-h10; no workaround is available. Palo Alto is not aware of malicious exploitation but classifies remediation urgency as highest.
Weekly Cybersecurity Newsletter Bulletin – Microsoft 0-day, FortiOS, PAN-OS Flaw, Revolut Data Breach, and 20+ Stories
Weekly roundup: Microsoft patches 973 flaws including two actively exploited zero-days; FortiOS CAPWAP flaw deploys PivotC2 RAT; PAN-OS root RCE disclosed.
Microsoft's September 2026 Patch Tuesday fixed 973 vulnerabilities, including two zero-days under active exploitation: CVE-2026-85880 (Windows ALPC) and CVE-2026-81963 (Windows Update Stack), both elevation-of-privilege bugs. SOCRadar reported active exploitation of CVE-2025-25249 (CVSS 9.8) in FortiOS CAPWAP, deploying a Node.js RAT called PivotC2 that exfiltrates Exchange mailboxes to Wasabi cloud storage; 178 devices were compromised out of 30,000 scanned IPs, attributed to a Russian-speaking financially motivated group. Palo Alto disclosed CVE-2026-0310, a 9.2-rated buffer overflow enabling root code execution on PA-Series firewalls, and Fortinet disclosed CVE-2026-84393, a ZTNA certificate validation MITM flaw. Cyera also revealed CVE-2026-6471 ('PostGREShell'), a 12-year-old PostgreSQL logical-decoding flaw allowing code execution via REPLICATION-privileged accounts.
2026-006: Critical Vulnerability in PAN-OS
Palo Alto Networks PAN-OS User-ID Authentication Portal flaw allows unauthenticated root RCE; limited exploitation observed and patches still pending.
Palo Alto Networks disclosed CVE-2026-0300 (CVSS 9.3), a buffer overflow in the PAN-OS User-ID Authentication Portal (Captive Portal) that enables unauthenticated arbitrary code execution with root privileges on PA-Series and VM-Series firewalls. Only appliances configured to use the Authentication Portal are affected. Palo Alto observed limited exploitation; at publication patches were not yet available, so restricting portal access to trusted zones or disabling it was recommended as mitigation.