Cyber Resilience

CVE-2024-40766

CriticalCISA KEVActive ExploitationEUVD ExploitedRansomware-linked

Published: 23 August 2024

Published
23 August 2024
Modified
31 October 2025
KEV Added
09 September 2024
Patch
CVSS Score v3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0344 87.8th percentile
Risk Priority 42 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2024-40766 is a critical-severity Improper Access Control (CWE-284) vulnerability in Sonicwall Sonicos. Its CVSS base score is 9.8 (Critical).

Operationally, ranked in the top 12.2% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog.

Deeper analysis

An improper access control vulnerability exists in the SonicWall SonicOS management interface that can permit unauthorized resource access and, under certain conditions, trigger a firewall crash. The flaw affects SonicWall Firewall devices running Gen 5 and Gen 6 firmware as well as Gen 7 devices on SonicOS 7.0.1-5035 and earlier releases. The issue carries a CVSS 3.1 base score of 9.8, reflecting network-accessible exploitation without authentication or user interaction.

An unauthenticated remote attacker can send specially crafted requests to the management access component to bypass access controls, potentially obtaining sensitive configuration data or disrupting device availability. Because the vector requires no credentials, the exposure extends to any internet-facing SonicWall appliance whose management services are reachable.

The vendor advisory SNWLID-2024-0015 and the CISA Known Exploited Vulnerabilities catalog both list the issue, confirming that public exploitation has been observed. Administrators are advised to apply the patches or configuration mitigations published by SonicWall for the affected firmware branches.

EPSS for the CVE rose from a low baseline to a peak of 0.0908 on 2025-12-11 before receding to the current value of 0.0344, indicating that exploitation interest increased after disclosure.

EU & UK References

Vulnerability details

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,…

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as well as Gen 7 devices running SonicOS 7.0.1-5035 and older versions.

CWE(s)
KEV Date Added
09 September 2024

Related Threats

Threat-Actor AttributionAI

Akira (G1024)
Akira ransomware exploited this SonicWall SSLVPN flaw (CISA KEV ransomware-use noted; vendor and CISA reporting).

Affected Assets

sonicwall
sonicos
≤ 5.9.2.14-13o · ≤ 6.5.2.8-2n · ≤ 6.5.4.15.116n

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-284

The access control policy and procedures directly mandate and enforce proper access control mechanisms across the organization.

addresses: CWE-284

Device lock enforces restricted access until re-authentication, directly reducing unauthorized use of active sessions.

addresses: CWE-284

Supervision and review of access control activities directly detects and remediates improper access configurations or usages.

addresses: CWE-284

Explicitly identifying and documenting actions permitted without identification or authentication enforces proper access control boundaries by defining justified exceptions.

addresses: CWE-284

By automatically labeling outputs with security attributes, the control supports attribute-based enforcement and reduces exploitability of improper access control weaknesses.

addresses: CWE-284

Associating and retaining security attributes with data directly supports enforcement of access control decisions across storage, processing, and transmission.

addresses: CWE-284

Requiring prior authorization for each remote access type prevents improper access control over remote connections.

addresses: CWE-284

Requiring authorization of wireless access before allowing connections enforces proper access control for this access method.

References