In late July 2025, Arctic Wolf observed an increase in ransomware activity targeting SonicWall firewall devices for initial access. In the intrusions reviewed, multiple pre-ransomware intrusions were observed within a short period of time, each involving VPN access through SonicWall SSL VPNs.
While credential access through brute force, dictionary attacks, and credential stuffing have not yet been definitively ruled out in all cases, available evidence points to the existence of a zero-day vulnerability. In some instances, fully patched SonicWall devices were affected following credential rotation. Despite TOTP MFA being enabled, accounts were still compromised in some instances.
Read more…
Source: Arctic Wolf
Sign up for the Cyber Security Review Newsletter
The latest cyber security news and insights delivered right to your inbox
Related:
- D-Link router riddled with 0-day flaws
September 12, 2017
A security researcher has shamed D‑Link by publicly disclosing 10 serious, as-yet unpatched vulnerabilities in a line of consumer-grade routers without notifying the vendor first. Security researcher Pierre Kim went public on a series of flaws in D‑Link DIR 850L wireless AC1200 dual-band gigabit cloud routers without disclosing the issue to D‑Link beforehand because of a ...
- WikiLeaks Vault 7: CIA’s “Pandemic” Tool Replaces Files with Malware
June 2, 2017
WikiLeaks has released a new set of documents from its Vault 7 series, this time detailing a tool that the CIA allegedly uses to spread malware on a targeted organization’s network. Appropriately called “Pandemic,” the tool can install a file system filter driver on a network, replacing legitimate files with malicious payload when they are accessed ...
- Russian-controlled telecom hijacks financial services’ Internet traffic
April 28, 2017
On Wednesday, large chunks of network traffic belonging to MasterCard, Visa, and more than two dozen other financial services companies were briefly routed through a Russian government-controlled telecom under unexplained circumstances that renew lingering questions about the trust and reliability of some of the most sensitive Internet communications. Anomalies in the border gateway protocol—which routes large-scale ...
- Router Vulnerabilities Disclosed in July Remain Unpatched
January 17, 2017
Details on serious vulnerabilities in a number of routers freely distributed by a major Thai ISP were published on Monday after private disclosures made to the vendors in July went unanswered. Researcher Pedro Ribeiro of Agile Information Security found accessible admin accounts and command injection vulnerabilities in ZyXel and Billion routers distributed by TrueOnline, Thailand’s largest ...