Full Report
Palo Alto Networks has released security updates for a high-severity security flaw impacting GlobalProtect Gateway and Portal, for which it said there exists a proof-of-concept (PoC) exploit. The vulnerability, tracked as CVE-2026-0227 (CVSS score: 7.7), has been described as a denial-of-service (DoS) condition impacting GlobalProtect PAN-OS software arising as a result of an improper check for
Analysis Summary
# Vulnerability: Denial-of-Service in Palo Alto Networks GlobalProtect (PAN-OS)
## CVE Details
- CVE ID: CVE-2026-0227
- CVSS Score: 7.7 (High)
- CWE: CWE-754 (Improper Check for Exceptional Conditions)
## Affected Systems
- Products: PAN-OS (for NGFW and Prisma Access), Prisma Access
- Versions:
- PAN-OS 12.1 < 12.1.3-h3, < 12.1.4
- PAN-OS 11.2 < 11.2.4-h15, < 11.2.7-h8, < 11.2.10-h2
- PAN-OS 11.1 < 11.1.4-h27, < 11.1.6-h23, < 11.1.10-h9, < 11.1.13
- PAN-OS 10.2 < 10.2.7-h32, < 10.2.10-h30, < 10.2.13-h18, < 10.2.16-h6, < 10.2.18-h1
- PAN-OS 10.1 < 10.1.14-h20
- Prisma Access 11.2 < 11.2.7-h8
- Prisma Access 10.2 < 10.2.10-h29
- Configurations: Only applicable to configurations with an enabled GlobalProtect gateway or portal. Cloud NGFW is not impacted.
## Vulnerability Description
A denial-of-service (DoS) vulnerability exists in the GlobalProtect feature of PAN-OS software due to an improper check for exceptional conditions. This flaw allows an unauthenticated attacker to send specially crafted requests that trigger the condition, resulting in the firewall entering into a maintenance mode and effectively crashing the service or device. Repeated attempts can sustain the denial of service.
## Exploitation
- Status: PoC available
- Complexity: Not explicitly stated, but DoS against network infrastructure often suggests low or medium complexity when successful exploits are shared.
- Attack Vector: Network (Unauthenticated remote access required, targeting the GlobalProtect interface).
## Impact
- Confidentiality: Low (DoS does not directly expose data listed in the context)
- Integrity: Medium (Service disruption affects management functions)
- Availability: High (Firewall or services enter maintenance mode, causing denial of service)
## Remediation
### Patches
Palo Alto Networks has released security updates addressing this issue. Customers should upgrade to versions equal to or higher than the fixed versions listed in the vendor advisory.
### Workarounds
- There are **no workarounds** available to mitigate this specific flaw. Immediate patching is required.
## Detection
- **Indicators of Compromise (IoCs):** Frequent, repetitive connection attempts targeting the GlobalProtect gateway/portal interface that correlate with device/service instability or subsequent maintenance mode entries.
- **Detection Methods and Tools:** Monitor firewall logs for unusual traffic patterns directed at GlobalProtect endpoints. Review system logs for entries indicating the firewall entering maintenance mode unexpectedly.
## References
- Vendor Advisory: [security.paloaltonetworks.com/CVE-2026-0227](https://security.paloaltonetworks.com/CVE-2026-0227) (Defanged)