Palo Alto warns of critical firewall flaw, tells users a patch is on the way
- A critical buffer overflow flaw (CVE‑2026‑0300) in PAN‑OS User‑ID Authentication Portal is under limited exploitation
- The bug allows unauthenticated code execution with root privileges on exposed firewalls
- Palo Alto advised restricting portals to trusted networks; fixes are due May 13, 2026
PAN-OS User-ID Authentication Portal, a feature in Palo Alto Networks firewalls that identifies and authenticates users on a network, contains a critical-severity zero-day vulnerability which is being exploited in limited attacks, the company has warned.
The bug is described as a buffer overflow weakness that allows unauthenticated threat actors to run arbitrary code with root privileges on PA-Series and VM-Series firewalls via specially crafted packets.
It is tracked as CVE-2026-0300 and was given a severity score of 9.3/10 (critical). It only works against endpoints that are exposed to the public internet.
Guidance and patches
"Limited exploitation has been observed targeting Palo Alto Networks User-ID™ Authentication Portals that are exposed...
Copyright of this story solely belongs to techradar.com. To see the full text click HERE
