CVE-2024-40766
SonicWall SonicOS Improper Access Control Vulnerability
SonicWall SonicOS
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.
Ransomware groups exploiting CVE-2024-40766
The Akira ransomware group is said to have emerged in March 2023, and there's much speculation about its ties to the former CONTI ransomware group. It's worth noting that with the end of CONTI's operation, several affiliates migrated to independent campaigns s
Sinobi is a private vetted-affiliate RaaS group that emerged in mid-2025, believed to be a rebrand of the Lynx/INC ransomware lineage, claiming 176 victims by end of 2025 through double-extortion attacks primarily against mid-market US organizations via compro
Exploitation is attributed to these groups across their recorded activity. It does not follow that every organisation they listed was reached through CVE-2024-40766 — the source data does not record an entry point per incident.
Exploitation status
CISA Known Exploited Vulnerabilities
Listed by CISA on 9 September 2024. US federal agencies were required to remediate it by 30 September 2024. CISA records this vulnerability as known to be used in ransomware campaigns.
EPSS — exploitation probability
FIRST puts the probability of exploitation activity in the next 30 days at 18.2%, which is higher than 96.9% of all scored vulnerabilities. EPSS is a forecast of activity, not a measure of severity, and it is rescored daily.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Recent listings by these groups
Disclosures from the groups above, newest first.
Frequently asked questions
Is CVE-2024-40766 being exploited by ransomware groups?
Yes. CVE-2024-40766 is recorded as exploited by Akira, Sinobi. Between them these groups account for 1,681 victim disclosures in this database. CISA also records this vulnerability as used in ransomware campaigns.
What does CVE-2024-40766 affect?
CVE-2024-40766 affects SonicWall SonicOS. 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.
How severe is CVE-2024-40766?
CVE-2024-40766 is rated CRITICAL with a CVSS base score of 9.8. EPSS puts the probability of exploitation in the next 30 days at 18.2%, higher than 96.9% of all scored vulnerabilities. It is listed in the CISA Known Exploited Vulnerabilities catalog, with a federal remediation deadline of 30 September 2024.
How should organisations respond to CVE-2024-40766?
Apply the vendor patch for SonicWall SonicOS as the first priority, and treat any internet-facing instance as the most urgent. Because this vulnerability is associated with ransomware activity, also review whether the affected systems were reachable before patching, rather than assuming that patching alone closes the incident.