Insights

Drilling Down on Uncle Sam’s Proposed TP-Link Ban

The U.S. government is reportedly preparing to ban the sale of wireless routers and other networking gear from TP-Link Systems, a tech company that currently enjoys an estimated 50% market share among home users and small businesses. Experts say while the proposed ban may have more to do with TP-Link’s ties to China than any specific technical threats, much of the rest of the industry serving this market also sources hardware from China and ships…

Read More

Cloudflare Scrubs Aisuru Botnet from Top Domains List

For the past week, domains associated with the massive Aisuru botnet have repeatedly usurped Amazon, Apple, Google and Microsoft in Cloudflare’s public ranking of the most frequently requested websites. Cloudflare responded by redacting Aisuru domain names from their top websites list. The chief executive at Cloudflare says Aisuru’s overlords are using the botnet to boost their malicious domain rankings, while simultaneously attacking the company’s domain name system (DNS) service. The #1 and #3 positions in…

Read More

Alleged Jabber Zeus Coder ‘MrICQ’ in U.S. Custody

A Ukrainian man indicted in 2012 for conspiring with a prolific hacking group to steal tens of millions of dollars from U.S. businesses was arrested in Italy and is now in custody in the United States, KrebsOnSecurity has learned. Sources close to the investigation say Yuriy Igorevich Rybtsov, a 41-year-old from the Russia-controlled city of Donetsk, Ukraine, was previously referenced in U.S. federal charging documents only by his online handle “MrICQ.” According to a 13-year-old…

Read More

New Guidance Released on Microsoft Exchange Server Security Best Practices

Today, CISA, in partnership with the National Security Agency and international cybersecurity partners, released Microsoft Exchange Server Security Best Practices, a guide to help network defenders harden on-premises Exchange servers against exploitation by malicious actors. Threat activity targeting Exchange continues to persist, and organizations with unprotected or misconfigured Exchange servers remain at high risk of compromise.  Best practices in this guide focus on hardening user authentication and access, ensuring strong network encryption, and minimizing application…

Read More

Aisuru Botnet Shifts from DDoS to Residential Proxies

Aisuru, the botnet responsible for a series of record-smashing distributed denial-of-service (DDoS) attacks this year, recently was overhauled to support a more low-key, lucrative and sustainable business: Renting hundreds of thousands of infected Internet of Things (IoT) devices to proxy services that help cybercriminals anonymize their traffic. Experts say a glut of proxies from Aisuru and other sources is fueling large-scale data harvesting efforts tied to various artificial intelligence (AI) projects, helping content scrapers evade…

Read More

Microsoft Releases Out-of-Band Security Update to Mitigate Windows Server Update Service Vulnerability, CVE-2025-59287

Microsoft released an update to address a critical remote code execution vulnerability impacting Windows Server Update Service (WSUS) in Windows Server (2012, 2016, 2019, 2022, and 2025), CVE-2025-59287, that a prior update did not fully mitigate.  CISA strongly urges organizations to implement Microsoft’s updated Windows Server Update Service (WSUS) Remote Code Execution Vulnerability guidance, 1 or risk an unauthenticated actor achieving remote code execution with system privileges. Immediate actions for organizations with affected products are:…

Read More

Canada Fines Cybercrime Friendly Cryptomus $176M

Financial regulators in Canada this week levied $176 million in fines against Cryptomus, a digital payments platform that supports dozens of Russian cryptocurrency exchanges and websites hawking cybercrime services. The penalties for violating Canada’s anti money-laundering laws come ten months after KrebsOnSecurity noted that Cryptomus’s Vancouver street address was home to dozens of foreign currency dealers, money transfer businesses, and cryptocurrency exchanges — none of which were physically located there. On October 16, the Financial…

Read More

CISA Releases 10 Industrial Control Systems Advisories

CISA released 10 Industrial Control Systems (ICS) advisories. These advisories provide timely information about current security issues, vulnerabilities, and exploits surrounding ICS. ICSA-25-294-01 Rockwell Automation 1783-NATR ICSA-25-294-02 Rockwell Automation Compact GuardLogix 5370 ICSA-25-294-03 Siemens SIMATIC S7-1200 CPU V1/V2 Devices ICSA-25-294-04 Siemens RUGGEDCOM ROS Devices ICSA-25-294-05 CloudEdge Online Cameras and App ICSA-25-294-06 Raisecomm RAX701-GC Series ICSMA-25-294-01 Oxford Nanopore Technologies MinKNOW ICSA-25-035-07 Schneider Electric Pro-Face GP-Pro EX and Remote HMI (Update A) ICSA-24-354-07 Schneider Electric Modicon Controllers…

Read More

Email Bombs Exploit Lax Authentication in Zendesk

Cybercriminals are abusing a widespread lack of authentication in the customer service platform Zendesk to flood targeted email inboxes with menacing messages that come from hundreds of Zendesk corporate customers simultaneously. Zendesk is an automated help desk service designed to make it simple for people to contact companies for customer support issues. Earlier this week, KrebsOnSecurity started receiving thousands of ticket creation notification messages through Zendesk in rapid succession, each bearing the name of different…

Read More

CISA Directs Federal Agencies to Mitigate Vulnerabilities in F5 Devices

Today, CISA issued Emergency Directive ED 26-01: Mitigate Vulnerabilities in F5 Devices to direct Federal Civilian Executive Branch agencies to inventory F5 BIG-IP products, evaluate if the networked management interfaces are accessible from the public internet, and apply newly released updates from F5.  A nation-state affiliated cyber threat actor has compromised F5 systems and exfiltrated data, including portions of the BIG-IP proprietary source code and vulnerability information, which provides the actor with a technical advantage…

Read More