VULNERABILITY INTELLIGENCE

CVE-2026-0300

CVSS score9.8 CRITICAL
EPSS probability41.71%
CISA KEVKnown exploited vulnerability
Published2026-05-06
Last modified2026-10-26
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Known Exploited Vulnerability

Palo Alto Networks PAN-OS Out-of-bounds Write Vulnerability

Vendor / product: Palo Alto Networks / PAN-OS

Description

A buffer overflow vulnerability in the User-ID™ Authentication Portal (aka Captive Portal) service of Palo Alto Networks PAN-OS software allows an unauthenticated attacker to execute arbitrary code with root privileges on the PA-Series and VM-Series firewalls by sending specially crafted packets. The risk of this issue is greatly reduced if you secure access to the User-ID™ Authentication Portal per the best practice guidelines https://knowledgebase.paloaltonetworks.com/KCSArticleDetail by restricting access to only trusted internal IP addresses. Prisma Access, Cloud NGFW and Panorama appliances are not impacted by this vulnerability.

Weakness classification

  • psirt@paloaltonetworks.com: CWE-787

Primary references