CVE-2024-40766 — SonicWall SonicOS

As of 2025-10-21, CVE-2024-40766 is a CRITICAL-severity vulnerability in SonicWall SonicOS, CVSS v3.1 9.3, EPSS 3.5% (87.8th percentile). It is listed in the CISA Known Exploited Vulnerabilities catalog (added 2024-09-09), with a US federal remediation deadline of 2024-09-30, and CISA links it to known ransomware campaigns. Threadlinqs Intelligence links 3 tracked threat campaigns to CVE-2024-40766, most recently “SEO Poisoning Supply Chain Campaign Distributing Akira Ransomware via Trojanized Enterprise Software”.

Last updated: 2025-10-21

What is CVE-2024-40766?

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.

The record classifies CVE-2024-40766 under weakness class CWE-284. Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs no prior authentication, needs no user interaction, and has high impact on confidentiality. 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 751 days ago.

Severity and exploitation probability

CVSS v3.1 base score

9.3 — CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:L

EPSS (FIRST)

3.5% probability of exploitation in the next 30 days, higher than 87.8% of all scored CVEs

CISA KEV

Listed since 2024-09-09, federal remediation deadline 2024-09-30 — used in known ransomware campaigns

Threadlinqs priority

10/10 — CISA lists it as used in ransomware, which Threadlinqs scores at the maximum

Published

2024-08-23, last modified 2025-10-21

Is CVE-2024-40766 being exploited?

CISA added CVE-2024-40766 to the Known Exploited Vulnerabilities catalog on 2024-09-09, which means the agency holds evidence of exploitation in the wild; US federal civilian agencies had to remediate it by 2024-09-30 under BOD 22-01. CISA flags the vulnerability as one used in known ransomware campaigns. It currently carries a trending score of 37 in the Threadlinqs vulnerability feed.

Affected products and versions

• SonicWall: SonicOS

How to fix CVE-2024-40766

Because CVE-2024-40766 is KEV-listed, US federal civilian agencies were required to apply the vendor fix, or stop using the product, by 2024-09-30. No vendor patch reference has been recorded for CVE-2024-40766 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.

Threat activity tracking CVE-2024-40766

3 tracked threats in the Threadlinqs corpus reference CVE-2024-40766, either in the campaign’s CVE list or as an indicator on the campaign record.

• SEO Poisoning Supply Chain Campaign Distributing Akira Ransomware via Trojanized Enterprise Software — CRITICAL · 2026-06-30
• Akira Ransomware Kill Chain — SSLVPN Credential Stuffing → Kerberoasting → RDP Lateral → vssadmin Shadow Copy Deletion (SANS ISC Forensic Reconstruction, May 2026) — HIGH · 2026-05-27
• Coordinated Reconnaissance Campaign Maps SonicWall SSL VPN Attack Surface via Commercial Proxy Infrastructure (84,142 Sessions / 4,305 IPs / 20 ASNs) — HIGH · 2026-02-25

Sources

Seeded from cveorg and not yet processed by the Threadlinqs enrichment pipeline, so blank CVSS, EPSS or KEV fields above mean NOT MEASURED rather than measured-absent.

• psirt.global.sonicwall.com

← all vulnerabilities · Markdown version · Threadlinqs Intelligence