← All CVEs

CVE-2026-0300

critical · 9.3Actively exploited

On the CISA Known Exploited Vulnerabilities catalog

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.

Added 2026-05-06Remediation due 2026-05-09

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.

9.3
CVSS
31.7%
EPSS (exploit prob.)
98th
EPSS percentile
2026-05-06
Published

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

Weaknesses

CWE-787

Affected products

VendorProductAffected versions
paloaltonetworkspan-os10.2.0
paloaltonetworkspan-os10.2.1
paloaltonetworkspan-os10.2.2
paloaltonetworkspan-os10.2.3
paloaltonetworkspan-os10.2.4
paloaltonetworkspan-os10.2.5
paloaltonetworkspan-os10.2.6
paloaltonetworkspan-os10.2.7
paloaltonetworkspan-os10.2.7
paloaltonetworkspan-os10.2.7
paloaltonetworkspan-os10.2.7
paloaltonetworkspan-os10.2.7
paloaltonetworkspan-os10.2.7
paloaltonetworkspan-os10.2.7
paloaltonetworkspan-os10.2.7
paloaltonetworkspan-os10.2.7
paloaltonetworkspan-os10.2.7
paloaltonetworkspan-os10.2.7
paloaltonetworkspan-os10.2.8
paloaltonetworkspan-os10.2.9
paloaltonetworkspan-os10.2.10
paloaltonetworkspan-os10.2.10
paloaltonetworkspan-os10.2.10
paloaltonetworkspan-os10.2.10
paloaltonetworkspan-os10.2.10
paloaltonetworkspan-os10.2.10
paloaltonetworkspan-os10.2.10
paloaltonetworkspan-os10.2.10
paloaltonetworkspan-os10.2.10
paloaltonetworkspan-os10.2.10
paloaltonetworkspan-os10.2.10
paloaltonetworkspan-os10.2.10
paloaltonetworkspan-os10.2.10
paloaltonetworkspan-os10.2.10
paloaltonetworkspan-os10.2.10
paloaltonetworkspan-os10.2.10
paloaltonetworkspan-os10.2.11
paloaltonetworkspan-os10.2.12
paloaltonetworkspan-os10.2.13
paloaltonetworkspan-os10.2.13

Check a specific version with /api/v1/cve/match.

References

Query this programmatically:

curl https://evil-db.io/api/v1/cve/CVE-2026-0300