Palo Alto Networks PAN-OS 10.2.x / 11.1.x / 11.2.x / 12.1.x Vulnerability

high Nessus Plugin ID 312282

Synopsis

The remote PAN-OS host is affected by a vulnerability

Description

The version of Palo Alto Networks PAN-OS running on the remote host is a vulnerable version of 10.2.x, 11.1.x, 11.2.x, or 12.1.x. It is, therefore, affected by a vulnerability.

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?id=kA14u000000CqbiCAC) by restricting access to only trusted internal IP addresses.

Prisma Access, Cloud NGFW and Panorama appliances are not impacted by this vulnerability.

Tenable has extracted the preceding description block directly from the PAN-OS security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

Solution

Upgrade to a fixed version

Plugin Details

Severity: High

ID: 312282

File Name: palo_alto_CVE-2026-0300.nasl

Version: 1.1

Type: Combined

Published: 5/5/2026

Updated: 5/5/2026

Configuration: Enable paranoid mode

Supported Sensors: Nessus

Risk Information

CVSS v2

Risk Factor: Critical

Base Score: 10

Temporal Score: 7.4

Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:C

CVSS Score Source: CVE-2026-0300

CVSS v3

Risk Factor: Critical

Base Score: 9.8

Temporal Score: 8.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

CVSS v4

Risk Factor: High

Base Score: 8.7

Threat Score: 6.3

Threat Vector: CVSS:4.0/E:U

Vector: CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:L/SI:L/SA:N

Vulnerability Information

CPE: cpe:/o:paloaltonetworks:pan-os

Required KB Items: Host/Palo_Alto/Firewall/Version, Host/Palo_Alto/Firewall/Full_Version, Host/Palo_Alto/Firewall/Source, Settings/ParanoidReport

Exploit Ease: No known exploits are available

Patch Publication Date: 5/5/2026

Vulnerability Publication Date: 5/5/2026

Reference Information

CVE: CVE-2026-0300

CWE: 787