CVE-2024-40766 SonicWall SonicOS Improper Access Control Vulnerability
SonicWall SonicOS contains an improper access control vulnerability that could lead to unauthorized resource access and, under certain conditions, may cause the firewall to crash.
From the CISA KEV catalogue version 2026.11.06, with Cybergen analysis. Updated 6 Nov 2026.
Should You Worry?
- CISA confirmed exploitation in the wild and added it to the Known Exploited Vulnerabilities catalogue on 9 Sep 2024.
- CISA lists it as known to be used in ransomware campaigns.
- Rated Critical severity (CVSS 9.3, scored by CISA).
- This product type is often exposed to the internet, which is where attackers scan for it first.
- Named in Cybergen threat actor reporting: Akira, SafePay, Sinobi.
- It has been in the catalogue for 788 days. Systems still unpatched now have almost certainly been scanned for it.
What It Is
An improper access control vulnerability has been identified in the SonicWall SonicOS management access, potentially leading to unauthorized resource access and in specific conditions, causing the firewall to crash. This issue affects SonicWall Firewall Gen 5 and Gen 6 devices, as well as Gen 7 devices running SonicOS 7.0.1-5035 and older versions.
Affected Versions
| Product | Versions |
|---|---|
| SonicWall SonicOS | 5.9.2.14-12o and older versions 6.5.4.14-109n and older versions 7.0.1-5035 and older versions |
From the public CVE record, as supplied by the vendor. Always confirm against the vendor advisory.
What To Do Now
- 1
Find it
Search your asset inventory and external attack surface for SonicWall SonicOS. Include cloud images, appliances and anything a supplier runs for you.
Attack Surface Management - 2
Fix it
Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
Vulnerability Management - 3
Hunt for compromise
If an affected system was reachable before you patched, assume it may have been hit. Check logs, new accounts, web shells and outbound connections from the date of exposure.
Incident Response - 4
Prove it is fixed
Rescan or test the system after patching. Upgrades that fail silently and forgotten secondary instances are common.
Penetration Testing
The Compliance Clock
General guidance, not legal advice. Your obligations depend on your sector, scope and jurisdiction.
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