Dec 27, 2024Ravie LakshmananFirewall Security / Vulnerability

Palo Alto Networks has disclosed a high-severity vulnerability impacting PAN-OS software that could cause a denial-of-service (DoS) condition on susceptible devices.

The flaw, tracked as CVE-2024-3393 (CVSS score: 8.7), impacts PAN-OS versions 10.X and 11.X, as well as Prisma Access running PAN-OS versions. It has been addressed in PAN-OS 10.1.14-h8, PAN-OS 10.2.10-h12, PAN-OS 11.1.5, PAN-OS 11.2.3, and all later PAN-OS versions.

“A denial-of-service vulnerability in the DNS Security feature of Palo Alto Networks PAN-OS software allows an unauthenticated attacker to send a malicious packet through the data plane of the firewall that reboots the firewall,” the company said in a Friday advisory.

“Repeated attempts to trigger this condition will cause the firewall to enter maintenance mode.”

Palo Alto Networks said it discovered the flaw in production use, and that it’s aware of customers “experiencing this denial-of-service (DoS) when their firewall blocks malicious DNS packets that trigger this issue.”

The extent of the activity is presently unknown. The Hacker News has reached out to Palo Alto Networks for further comment, and we will update the story if we hear back.

It’s worth pointing out that firewalls that have the DNS Security logging enabled are affected by CVE-2024-3393. The severity of the flaw also drops to a CVSS score of 7.1 when access is only provided to authenticated end users via Prisma Access.

The fixes have also been extended to other commonly deployed maintenance releases –

• PAN-OS 11.1 (11.1.2-h16, 11.1.3-h13, 11.1.4-h7, and 11.1.5)
• PAN-OS 10.2 (10.2.8-h19, 10.2.9-h19, 10.2.10-h12, 10.2.11-h10, 10.2.12-h4, 10.2.13-h2, and 10.2.14)
• PAN-OS 10.1 (10.1.14-h8 and 10.1.15)
• PAN-OS 10.2.9-h19 and 10.2.10-h12 (only applicable to Prisma Access)
• PAN-OS 11.0 (No fix owing to it reaching end-of-life status on November 17, 2024)

As workarounds and mitigations for unmanaged firewalls or those managed by Panorama, customers have the option of setting Log Severity to “none” for all configured DNS Security categories for each Anti-Spyware profile by navigating to Objects > Security Profiles > Anti-spyware > (select a profile) > DNS Policies > DNS Security.

For firewalls managed by Strata Cloud Manager (SCM), users can either follow the above steps to disable DNS Security logging directly on each device, or across all of them by opening a support case. For Prisma Access tenants managed by SCM, it’s recommended to open a support case to turn off logging until an upgrade is carried out.