CVE-2026-0300: Palo Alto Networks PAN-OS Out-of-bounds Write
Palo Alto Networks PAN-OS Out-of-bounds Write Vulnerability. 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.
- CISA KEV-listed (remediation due 2026-05-09)
- EPSS 32.1% (98.2% percentile)
- CVSS 9.3 critical
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