{
    "id": "CVE-2026-0300",
    "published": "2026-05-06 19:16:35",
    "last_modified": "2026-06-17 10:10:43",
    "cvss_score": "9.8",
    "cvss_severity": "CRITICAL",
    "cvss_version": "3.1",
    "cvss_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
    "cwe": "CWE-787",
    "description": "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. \n\nThe 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  by restricting access to only trusted internal IP addresses.\n\nPrisma Access, Cloud NGFW and Panorama appliances are not impacted by this vulnerability.",
    "epss_score": "0.31725",
    "epss_percentile": "0.98241",
    "kev": 1,
    "kev_due": "2026-05-09",
    "has_exploit": 0,
    "updated_at": "2026-09-26 18:42:17",
    "priority": {
        "rank": 1,
        "label": "Patch first",
        "why": "On CISA KEV — known exploited in the wild, due 2026-05-09."
    },
    "products": [
        {
            "vendor": "paloaltonetworks",
            "product": "pa-1410"
        },
        {
            "vendor": "paloaltonetworks",
            "product": "pa-1420"
        },
        {
            "vendor": "paloaltonetworks",
            "product": "pa-3410"
        },
        {
            "vendor": "paloaltonetworks",
            "product": "pa-3420"
        },
        {
            "vendor": "paloaltonetworks",
            "product": "pa-3430"
        },
        {
            "vendor": "paloaltonetworks",
            "product": "pa-3440"
        },
        {
            "vendor": "paloaltonetworks",
            "product": "pa-410"
        },
        {
            "vendor": "paloaltonetworks",
            "product": "pa-410r"
        },
        {
            "vendor": "paloaltonetworks",
            "product": "pa-410r-5g"
        },
        {
            "vendor": "paloaltonetworks",
            "product": "pa-415"
        },
        {
            "vendor": "paloaltonetworks",
            "product": "pa-415-5g"
        },
        {
            "vendor": "paloaltonetworks",
            "product": "pa-440"
        },
        {
            "vendor": "paloaltonetworks",
            "product": "pa-445"
        },
        {
            "vendor": "paloaltonetworks",
            "product": "pa-450"
        },
        {
            "vendor": "paloaltonetworks",
            "product": "pa-450r"
        },
        {
            "vendor": "paloaltonetworks",
            "product": "pa-450r-5g"
        },
        {
            "vendor": "paloaltonetworks",
            "product": "pa-455"
        },
        {
            "vendor": "paloaltonetworks",
            "product": "pa-455-5g"
        },
        {
            "vendor": "paloaltonetworks",
            "product": "pa-455r-5g"
        },
        {
            "vendor": "paloaltonetworks",
            "product": "pa-460"
        },
        {
            "vendor": "paloaltonetworks",
            "product": "pa-501"
        },
        {
            "vendor": "paloaltonetworks",
            "product": "pa-505"
        },
        {
            "vendor": "paloaltonetworks",
            "product": "pa-510"
        },
        {
            "vendor": "paloaltonetworks",
            "product": "pa-520"
        },
        {
            "vendor": "paloaltonetworks",
            "product": "pa-540"
        },
        {
            "vendor": "paloaltonetworks",
            "product": "pa-5410"
        },
        {
            "vendor": "paloaltonetworks",
            "product": "pa-5420"
        },
        {
            "vendor": "paloaltonetworks",
            "product": "pa-5430"
        },
        {
            "vendor": "paloaltonetworks",
            "product": "pa-5440"
        },
        {
            "vendor": "paloaltonetworks",
            "product": "pa-5445"
        },
        {
            "vendor": "paloaltonetworks",
            "product": "pa-545-poe"
        },
        {
            "vendor": "paloaltonetworks",
            "product": "pa-5450"
        },
        {
            "vendor": "paloaltonetworks",
            "product": "pa-550"
        },
        {
            "vendor": "paloaltonetworks",
            "product": "pa-5540"
        },
        {
            "vendor": "paloaltonetworks",
            "product": "pa-555-poe"
        },
        {
            "vendor": "paloaltonetworks",
            "product": "pa-5550"
        },
        {
            "vendor": "paloaltonetworks",
            "product": "pa-5560"
        },
        {
            "vendor": "paloaltonetworks",
            "product": "pa-5570"
        },
        {
            "vendor": "paloaltonetworks",
            "product": "pa-5580"
        },
        {
            "vendor": "paloaltonetworks",
            "product": "pan-os"
        }
    ],
    "kev_detail": {
        "cve_id": "CVE-2026-0300",
        "date_added": "2026-05-06",
        "due_date": "2026-05-09",
        "vendor": "Palo Alto Networks",
        "product": "PAN-OS",
        "name": "Palo Alto Networks PAN-OS Out-of-bounds Write Vulnerability",
        "ransomware": 0
    },
    "exploits": [],
    "refs_list": [
        "https://security.paloaltonetworks.com/CVE-2026-0300",
        "https://cert-portal.siemens.com/productcert/html/ssa-967325.html",
        "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-0300"
    ]
}