CVE-2026-0300 Details
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.

The 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.

Prisma Access, Cloud NGFW and Panorama appliances are not impacted by this vulnerability.
View at NVD
Exploit prediction scoring system (EPSS) score for CVE-2026-0300
EPSS (Exploit Prediction Scoring System): EPSS predicts the likelihood that a vulnerability will be exploited in the wild. A higher percentage means a greater chance of an exploit occurring. The EPSS model produces a probability score between 0 and 1 (0 and 100%).
32.07 Probability of exploitation activity being observed over the next 30 days (98th percentile)
CVSS score for CVE-2026-0300
CVSS (Common Vulnerability Scoring System): An open framework owned and managed by FIRST.Org, Inc. that assigns a numerical score from 0 to 10 to software vulnerabilities to indicate their severity.
9.8 Critical
DVE Score by Bitsight AI
DVE scores complement traditional static scoring systems like CVSS with Bitsight AI powered real-time threat intelligence and underground cyber criminal activity so that security teams can reduce alert fatigue and focus on vulnerabilities most likely to be exploited.
Critical
More on DVE scores

CVE-2026-0300 Global Footprint

Top 10 Identified Countries

Country Observations Percentage
US 606 32.62%
IN 145 7.80%
DE 77 4.14%
CA 52 2.80%
GB 46 2.48%
JP 45 2.42%
FR 42 2.26%
AU 40 2.15%
CN 32 1.72%
PT 32 1.72%

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CVE-2026-0300 Industry Footprint

Top 10 Identified Industries

*Service provider organizations (typically Technology and Telecommunications) are disproportionally represented in the results given their upstream ownership of end-user infrastructure. See our FAQs.

Industry* Observations Percentage
Telecommunications 491 37.77%
Technology 337 25.92%
Finance 63 4.85%
Business Services 57 4.38%
Manufacturing 57 4.38%
Government/Politics 51 3.92%
Education 40 3.08%
Healthcare/Wellness 28 2.15%
Transportation 24 1.85%
Consumer Goods 24 1.85%

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