{"id":"CVE-2026-0300","vendor_project":"Palo Alto Networks","product":"PAN-OS","vulnerability_name":"Palo Alto Networks PAN-OS Out-of-bounds Write Vulnerability","date_added":"2026-05-06","due_date":"2026-05-09","known_ransomware_use":"Unknown","short_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.","required_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. 5/13/2026: Palo Alto has released a variety of patches. If these are relevant to your environment, please apply the designated patch.","cwes":"CWE-787","cvss_version":"4.0","cvss_severity":"CRITICAL","cvss_vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:L/SI:L/SA:N/E:A/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:Y/R:U/V:C/RE:M/U:Red","nvd_published":"2026-05-06","nvd_status":"Analyzed","epss":0.31725,"epss_percentile":0.98219,"cvss_score":9.3,"days_published_to_kev":0,"source":"https://data.cybermax-tools.workers.dev/cve/CVE-2026-0300","by":"CyberMax"}