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A Vulnerability in SonicOS Could Allow for Denial of Service (DoS)

Cisecurity • November 24, 2025

A vulnerability has been discovered SonicOS, which could allow for Denial of Service (DoS). SonicOS is the operating system that runs on SonicWall's network security appliances, such as firewalls. Successful exploitation of this vulnerability could allow a remote unauthenticated attacker to cause Denial of Service (DoS), which could cause an impacted firewall to crash. This vulnerability ONLY impacts the SonicOS SSLVPN interface or service if enabled on the firewall.

There are currently no reports of this vulnerability being exploited in the wild.

A vulnerability has been discovered SonicOS, which could allow for Denial of Service (DoS). Details of the vulnerability is as follows:

Tactic: Impact ( TA0040 ):

Technique : Endpoint Denial of Service ( T1499 ):

Successful exploitation of this vulnerability could allow a remote unauthenticated attacker to cause Denial of Service (DoS), which could cause an impacted firewall to crash.

We recommend the following actions be taken:

The full story

This article is one source in a clustered incident — the cluster page carries the summary, timeline and every other outlet covering it.

SonicWall SonicOS Flaw Allows Remote Firewall Crashes SonicWall has disclosed a critical vulnerability in its SonicOS SSLVPN service, tracked as CVE-2025-40601, which allows remote, unauthenticated attackers to crash Gen7 and Gen8 firewalls. The flaw, caused by a stack-based buffer overflow, poses significant risks for organizations using SonicWall for network security. SonicWall has urged customers to apply patches immediately, although there are currently no reports of active exploitation. 11 sources 23

Extracted Entities

A Vulnerability in SonicOS Could Allow for Denial of Service (DoS)

The full story

Extracted Entities

Attack Types (1)

MITRE ATT&CK (1)

Platforms (1)