CVE ID
CVE-2026-0300
Vulnerability Name
Palo Alto Networks PAN-OS Out-of-bounds Write Vulnerability
- Project: Palo Alto Networks
- Product: PAN-OS
Date
- Date Added: 2026-05-06
- Due Date: 2026-05-09
Description
Palo Alto Networks PAN-OS contains an out-of-bounds write vulnerability in the User-ID Authentication Portal (aka Captive Portal) service that can allow an unauthenticated attacker to execute arbitrary code with root privileges on the PA-Series and VM-Series firewalls by sending specially crafted packets.
Known To Be Used in Ransomware Campaigns?
Unknown
Action
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable. Until the vendor releases an official fix, the following workaround should be implemented: - Restrict User-ID Authentication Portal access to only trusted zones. - Disable User-ID Authentication Portal if not required.
Additional Notes
https://security.paloaltonetworks.com/CVE-2026-0300 ; https://nvd.nist.gov/vuln/detail/CVE-2026-0300
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