Palo Alto Networks PAN-OS Critical Vulnerability - 20260506001¶
Overview¶
Palo Alto Networks disclosed a critical buffer overflow vulnerability in the PAN‑OS User‑ID Authentication Portal (Captive Portal). An unauthenticated remote attacker can achieve arbitrary code execution with root privileges on PA‑Series and VM‑Series firewalls.
What is vulnerable?¶
| Product(s) Affected | Version(s) | CVE | CVSS | Severity |
|---|---|---|---|---|
| Palo Alto Networks PAN‑OS | Versions \<=12.1 | CVE-2026-0300 | 9.3 | Critical |
What has been observed?¶
The WASOC has not received any reports of exploitation of this vulnerability on Western Australian Government networks at the time of writing. However, limited exploitation has been observed targeting Palo Alto Networks User-ID authentication portals exposed to untrusted IP addresses and/or the public internet.
Recommendation¶
The WASOC recommends administrators apply the solutions as per vendor instructions to all affected devices within expected timeframes (refer Patch Management):
- Palo Alto Networks: https://security.paloaltonetworks.com/CVE-2026-0300