CVE-2026-0300

KEV
Published: Mag 06, 2026 Last Modified: Mag 06, 2026
ExploitDB:
Other exploit source:
Google Dorks:
CRITICAL 9,3
Attack Vector: network
Attack Complexity: low
Privileges Required: none
User Interaction: none
Confidentiality: N/A
Integrity: N/A
Availability: N/A

Description

AI Translation Available

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.

787

Out-of-bounds Write

Draft
Common Consequences
Security Scopes Affected:
Integrity Availability Other
Potential Impacts:
Modify Memory Execute Unauthorized Code Or Commands Dos: Crash, Exit, Or Restart Unexpected State
Applicable Platforms
Languages: Assembly, C, C++, Memory-Unsafe
Technologies: ICS/OT
View CWE Details
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026…
https://security.paloaltonetworks.com/CVE-2026-0300