Palo Alto Networks has patched a high‑severity PAN‑OS vulnerability (CVE‑2026‑0227, CVSS 7.7) that allows unauthenticated attackers to disrupt GlobalProtect VPN gateways and portals, potentially forcing affected firewalls into maintenance mode. Review this Cybersecurity Threat Advisory to protect your clients’ systems and mitigate your risk.
What is the threat?
CVE‑2026‑0227 is a denial‑of‑service vulnerability affecting PAN‑OS firewalls with GlobalProtect gateways or portals enabled on NGFW or Prisma Access. Attackers can trigger the issue without credentials or user interaction by sending simple network requests that disrupt remote access. Repeated attempts may push devices into maintenance mode, taking VPN services offline until manually restored.
The vulnerability stems from a logic/error‑handling flaw and impacts availability only. It requires GlobalProtect to be active. A public proof‑of‑concept exists, but no confirmed real‑world exploitation has been reported.
Why is it noteworthy?
GlobalProtect is widely deployed for remote access, making a low‑complexity, unauthenticated DoS especially disruptive. Automated attacks can repeatedly hit exposed gateways, triggering maintenance mode, failovers, and potential service degradation—even in high‑availability environments.
Although the bug does not compromise data or enable code execution, the operational impact can be significant: service outages, productivity loss, and increased load on IT teams. With no workaround and active internet scanning for vulnerable instances, prompt patching is critical.
What is the exposure or risk?
Organizations with internet‑facing GlobalProtect gateways or portals face elevated risk of VPN outages, failed logins, and temporary loss of remote access. The attack is trivial to automate and requires no credentials. High‑availability clusters may experience cascading failovers if repeatedly targeted.
While confidentiality and integrity are not at risk, recurring availability disruptions can delay incident response, impact SLAs, and force emergency operational changes. Prisma Access deployments with GlobalProtect are affected until patched; Cloud NGFW is not.
The public availability of exploit code increases the likelihood of opportunistic disruption.
What are the recommendations?
Barracuda advises organizations to take the following steps immediately:
- Patch to the latest fixed PAN‑OS or Prisma Access releases (no workarounds exist).
- Prioritize updates for internet‑exposed GlobalProtect gateways/portals and HA clusters.
- Limit access to GlobalProtect (IP allowlists, geofencing, or upstream rate‑limiting) where feasible until patches are applied.
- Monitor for DoS indicators: spikes in connection attempts, maintenance‑mode events, failovers, and service restarts; ensure alerting is enabled.
- Prepare and test recovery procedures for restoring devices from maintenance mode.
- Communicate patch timing and contingency plans to remote users and helpdesk teams.
- Validate GlobalProtect access, HA health, and continued resiliency after patching is complete.
References
For more in-depth information about the recommendations, please visit the following links:
If you have any questions about this Cybersecurity Threat Advisory, don’t hesitate to get in touch with Barracuda Managed XDR’s Security Operations Center.
This post originally appeared on Smarter MSP.