cve-2026-0300

{
  "cvss": 9.3,
  "datePublished": "2026-05-06",
  "dateUpdated": "2026-05-06",
  "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.",
  "dueDate": "2026-05-09",
  "id": "CVE-2026-0300",
  "kev_catalogs": [
    "cisa"
  ],
  "knownRansomwareCampaignUse": "Unknown",
  "notes": "https://security.paloaltonetworks.com/CVE-2026-0300 ; https://nvd.nist.gov/vuln/detail/CVE-2026-0300",
  "product": "PAN-OS",
  "requiredAction": "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.",
  "severity": "CRITICAL",
  "source": "cisa_known_exploited",
  "title": "Palo Alto Networks PAN-OS Out-of-bounds Write Vulnerability",
  "vendor": "Palo Alto Networks"
}