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July 22, 2020

Resurgence of Ursnif Banking Trojan "May's Most Wanted Malware"

The Ursnif banking trojan tries to blend into the network as legitimate Zoom and Webex activity, trying to capture credentials. See how Darktrace stops it!
Inside the SOC
Darktrace cyber analysts are world-class experts in threat intelligence, threat hunting and incident response, and provide 24/7 SOC support to thousands of Darktrace customers around the globe. Inside the SOC is exclusively authored by these experts, providing analysis of cyber incidents and threat trends, based on real-world experience in the field.
Written by
Max Heinemeyer
Global Field CISO
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22
Jul 2020

Earlier this month, Darktrace’s Cyber AI detected the Ursnif banking trojan, described as May’s most wanted malware, making a resurgence across its customers’ networks. This blog follows the malicious activity in one financial services company in the US, detailing how and why Darktrace Antigena stepped in and autonomously stopped the attack in real time.

Banking trojans continue to present a credible and persistent threat to organizations of all sizes across the globe. This attack was delivered via phishing email, which initiated a download of an executable file masquerading as a .cab extension.

This specific banking trojan is particularly sophisticated, with multiple new command and control (C2) domains registered – identifiable because several distinct Domain Generation Algorithms (DGA) were observed across different networks – the majority of which were only registered the day prior to the campaign.

Figure 1: A timeline of the attack

Phishing email catches organizations unaware

The malware itself was delivered via phishing email. The attack was not recognized by antivirus solutions at the time of delivery, slipping through the organization’s perimeter solutions and landing in employees’ inboxes. Unknowingly, an employee opened a disguised attachment containing macros, downloading an executable file masquerading as a .cab extension.

Interestingly, the malware also used new User Agents imitating Zoom and Webex, a clear attempt to blend in with assumed network traffic. After the malware was downloaded, several devices were observed making connections using these Zoom or Webex User Agents to non-Zoom and non-Webex domains, another attempt to blend in.

Figure 2: Darktrace’s Breach Event Log shows a number of models were triggered

Figure 3: Darktrace’s Device Event Log showing the device was connected to Outlook at the time of the executable file download

After the downloads, Darktrace’s AI observed beaconing to rare DGA domains. The majority of these domains were Russian and registered within the previous 24 hours.

Figure 4: A screenshot taken from one of the C2 domains observed, tobmojiol2adf[.]com, which appears to host a login page

Figure 5: The External Sites Summary of one of the C2 domains observed, tobmojiol2adf[.]com, which was identified as 100% rare for the network at the time of the model breach.

This attack managed to evade the rest of the organization’s security stack since the domains observed were recently registered and the majority of the file hashes and IoCs had not yet been flagged by OSINT tools, thus bypassing all signature-based detections. The initial file downloads also purported to be .cab files, but Darktrace’s AI identified that these were in fact executable files.

Multiple Darktrace detections, including the ‘Masqueraded File Transfer’ model and the ‘Initial Breach Chain Compromise’ model, alerted the security team to this activity. At the same time, the models triggered Darktrace’s Cyber AI Analyst to launch an automated investigation into the security incident, which surfaced additional vital information and dramatically reduced time to triage.

Figure 6: The Cyber AI Analyst output showing the subsequent C2 connections made by the device after the executable file download

Figure 7: Model breaches from the affected device, showing the malicious file download and subsequent command and control beaconing activity

Figure 8: Model Breach Event Log, showing Antigena’s response after the masqueraded file download and a new outbound connection

The case for Autonomous Response

The Ursnif banking trojan presents a particularly lethal threat: silent, stealthy, and capable of stealing vital financial information, email credentials, and other sensitive data at machine speeds. The rise of advanced malware like this demonstrates the need for security technology that can stay ahead of attackers. For this organization, the malware download and subsequent command and control activity could have represented the start of a costly attack.

Luckily the organization had Antigena Network installed in active mode. The C2 communications from infected devices were blocked seconds after the initial connection, preventing further C2 activity and the download of any additional malware. Using information surfaced by the Cyber AI Analyst, the security team could catch up and the threat was quickly contained.

This attack highlights the continuously evolving approaches used by malicious actors to evade detection. In the same week as the events explained above, Darktrace identified the Urnsnif malware in numerous other customers in the US and Italy, across multiple industries. Attackers are targeting businesses indiscriminately and are not slowing down.

Thanks to Darktrace analysts Grace Carballo and Hiromi Watanabe for their insights on the above threat find.

Technical details

IoCs:

Commenttobmojiol2adf[.]com – C2 domain, registered July 9
qumogtromb2a[.]com – Not yet registered
amehota2gfgh[.]com – C2 domain, registered July 8
gofast22gfor[.]com – C2 domain, registered July 8
xquptbabzxhxw[.]com – Not yet registered
e9bja[.]com

Masqueraded file download source9ygw2[.]com
Masqueraded file download sourcen2f79[.]com
Masqueraded file download sourceioyyf[.]com
Masqueraded file download sourcehq3ll[.]com
Masqueraded file download sourcehxxp://9ygw2[.]com/iz5/yaca.php?l=kpt1.cab
File path hxxp://e9bja[.]com/iz5/yaca.php?l=kpt4.cab
File path hxxp://n2f79[.]com/iz5/yaca.php?l=kpt1.cab
File path hxxp://ioyyf[.]com/iz5/yaca.php?l=kpt4.cab
File path hxxp://hq3ll[.]com/iz5/yaca.php?l=kpt12.cabFile path

MD5 hashes

  • fa6fc057b3c1bb1e84cc37dbd14e7c10
  • 37c28815f462115ff1439e251324ed5b
  • 40f69d093a720c338963bebb3e274593
  • 5602508f262b92f25dc36c4266f410b4
  • 619e5f5d56de5dfbe7b76bba924fd631
  • 30ea60c337c5667be79539f26b613449
  • 688380643b0d70a0191b7fbbea6fb313
  • 719f36d41379574569248e599767937f
  • 7a7ba75af1210e707c495990e678f83e
  • 7c4207591c6d07ce1c611a8bc4b61898
  • 8eec0a8518e87d7248d2882c6f05a551
  • 94915a540ce01fabec9ba1e7913837ea
  • 94e6d6c3cef950ed75b82428475681c7
  • bac0246599a070c8078a966d11f7089d
  • dc17489e558d0f07b016636bc0ab0dbe
  • dff18317acadc40e68f76d3b33ea4304
  • cee72b840f4e79ed5ffde7adc680a7cd

SHA1 hashes

  • 42dd5e8ad3f0d4de95eaa46eef606e24f3d253f0
  • 97d2158a44b0eaa2465f3062413427e33cc2ac50
  • 435c5ae175b40e5d64907bdb212290af607232eb
  • 4b9845e5e7475156efa468a4e58c3c72cf0d4e7e
  • a0494bf812cf1a5b075109fea1adc0d8d1f236f9
  • 297b1b5137249a74322330e80d478e68e70add0d
  • 46a9c4679169d46563cdebae1d38e4a14ed255c9
  • 4f4f65acf3a35da9b8da460cf7910cd883fe2e46
  • 60aee8045e0eb357b88db19775c0892f6bd388f1
  • 7d92dad4971d3c2abfc368a8f47049032ef4d8a9
  • 9631216035a58d1c3d4404607bd85bf0c80ccfe8
  • aab6a948d500de30b6b75a928f43891f5daaa2a8
  • c31dcf7bc391780ecf1403d504af5e844821e9a4
  • c41a9a7f416569a7f412d1a82a78f7977395ce2a
  • c7323a5596be025c693535fbb87b84beeacc7733
  • d64a6c135d7eac881db280c4cb04443b7d2e2a0b
  • 331ede8915e42d273722802a20e8bb9a448b39c5

Darktrace model breaches

  • Anomalous File/Masqueraded File Transfer
  • Compromise/ Sustained TCP Beaconing Activity to Rare Endpoint
  • Compromise/ HTTP Beaconing to Rare Destination
  • Compromise/ Slow Beaconing Activity to External rare
  • Compromise/ Beaconing Activity to External Rare
  • Device/ Initial Breach Chain Compromise
Inside the SOC
Darktrace cyber analysts are world-class experts in threat intelligence, threat hunting and incident response, and provide 24/7 SOC support to thousands of Darktrace customers around the globe. Inside the SOC is exclusively authored by these experts, providing analysis of cyber incidents and threat trends, based on real-world experience in the field.
Written by
Max Heinemeyer
Global Field CISO

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April 2, 2026

How Chinese-Nexus Cyber Operations Have Evolved – And What It Means For Cyber Risk and Resilience 

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Cybersecurity has traditionally organized risk around incidents, breaches, campaigns, and threat groups. Those elements still matter—but if we fixate on individual incidents, we risk missing the shaping of the entire ecosystem. Nation‑state–aligned operators are increasingly using cyber operations to establish long-term strategic leverage, not just to execute isolated attacks or short‑term objectives.  

Our latest research, Crimson Echo, shifts the lens accordingly. Instead of dissecting campaigns, malware families, or actor labels as discrete events, the threat research team analyzed Chinese‑nexus activity as a continuum of behaviors over time. That broader view reveals how these operators position themselves within environments: quietly, patiently, and persistently—often preparing the ground long before any recognizable “incident” occurs.  

How Chinese-nexus cyber threats have changed over time

Chinese-nexus cyber activity has evolved in four phases over the past two decades. This ranges from early, high-volume operations in the 1990s and early 2000s to more structured, strategically-aligned activity in the 2010s, and now toward highly adaptive, identity-centric intrusions.  

Today’s phase is defined by scale, operational restraint, and persistence. Attackers are establishing access, evaluating its strategic value, and maintaining it over time. This reflects a broader shift: cyber operations are increasingly integrated into long-term economic and geopolitical strategies. Access to digital environments, specifically those tied to critical national infrastructure, supply chains, and advanced technology, has become a form of strategic leverage for the long-term.  

How Darktrace analysts took a behavioral approach to a complex problem

One of the challenges in analyzing nation-state cyber activity is attribution. Traditional approaches often rely on tracking specific threat groups, malware families, or infrastructure. But these change constantly, and in the case of Chinese-nexus operations, they often overlap.

Crimson Echo is the result of a retrospective analysis of three years of anomalous activity observed across the Darktrace fleet between July 2022 and September 2025. Using behavioral detection, threat hunting, open-source intelligence, and a structured attribution framework (the Darktrace Cybersecurity Attribution Framework), the team identified dozens of medium- to high-confidence cases and analyzed them for recurring operational patterns.  

This long-horizon, behavior-centric approach allows Darktrace to identify consistent patterns in how intrusions unfold, reinforcing that behavioral patterns that matter.  

What the data shows

Several clear trends emerged from the analysis:

  • Targeting is concentrated in strategically important sectors. Across the dataset, 88% of intrusions occurred in organizations classified as critical infrastructure, including transportation, critical manufacturing, telecommunications, government, healthcare, and Information Technology (IT) services.  
  • Strategically important Western economies are a primary focus. The US alone accounted for 22.5% of observed cases, and when combined with major European economies including Germany, Italy, Spain and the UK, over half of all intrusions (55%) were concentrated in these regions.  
  • Nearly 63% of intrusions of intrusions began with the exploitation of internet-facing systems, reinforcing the continued risk posed by externally exposed infrastructure.  

Two models of cyber operations

Across the dataset, Chinese-nexus activity followed two operational models.  

The first is best described as “smash and grab.” These are short-horizon intrusions optimized for speed. Attackers move quickly – often exfiltrating data within 48 hours – and prioritize scale over stealth. The median duration of these compromises is around 10 days. It’s clear they are willing to risk detection for short-term gain.  

The second is “low and slow.” These operations were less prevalent in the dataset, but potentially more consequential. Here, attackers prioritize persistence, establishing durable access through identity systems and legitimate administrative tools, so they can maintain access undetected for months or even years. In one notable case, the actor had fully compromised the environment and established persistence, only to resurface in the environment more than 600 days after. The operational pause underscores both the depth of the intrusion and the actor’s long‑term strategic intent. This suggests that cyber access is a strategic asset to preserve and leverage over time, and we observed these attacks most often inin sectors of the high strategic importance.  

It’s important to note that the same operational ecosystem can employ both models concurrently, selecting the appropriate model based on target value, urgency, intended access. The observation of a “smash and grab” model should not be solely interpreted as a failure of tradecraft, but instead an operational choice likely aligned with objectives. Where “low and slow” operations are optimized for patience, smash and grab is optimized for speed; both seemingly are deliberate operational choices, not necessarily indicators of capability.  

Rethinking cyber risk

For many organizations, cyber risk is still framed as a series of discrete events. Something happens, it is detected and contained, and the organization moves on. But persistent access, particularly in deeply interconnected environments that span cloud, identity-based SaaS and agentic systems, and complex supply chain networks, creates a major ongoing exposure risk. Even in the absence of disruption or data theft, that access can provide insight into operations, dependencies, and strategic decision-making. Cyber risk increasingly resembles long-term competitive intelligence.  

This has impact beyond the Security Operations Center. Organizations need to shift how they think about governance, visibility, and resilience, and treat cyber exposure as a structural business risk instead of an incident response challenge.  

What comes next

The goal of this research is to provide a clearer understanding of how these operations work, so defenders can recognize them earlier and respond more effectively. That includes shifting from tracking indicators to understanding behaviors, treating identity providers as critical infrastructure risks, expanding supplier oversight, investing in rapid containment capabilities, and more.  

Learn more about the findings of Darktrace’s latest research, Crimson Echo: Understanding Chinese-nexus Cyber Operations Through Behavioral Analysis, by downloading the full report and summaries for business leaders, CISOs, and SOC analysts here.  

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About the author
Nathaniel Jones
VP, Security & AI Strategy, Field CISO

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April 1, 2026

AI-powered security for a rapidly growing grocery enterprise

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Protecting a complex, fast-growing retail organization

For this multi-banner grocery holding organization, cybersecurity is considered an essential business enabler, protecting operations, growth, and customer trust. The organization’s lean IT team manages a highly distributed environment spanning corporate offices, 100+ stores, distribution centers and  thousands of endpoints, users, and third-party connections.

Mergers and acquisitions fueled rapid growth, but they also introduced escalating complexity that constrained visibility into users, endpoints, and security risks inherited across acquired environments.

Closing critical visibility gaps with limited resources

Enterprise-wide visibility is a top priority for the organization, says the  Vice President of Information Technology. “We needed insights beyond the perimeter into how users and devices were behaving across the organization.”

A security breach that occurred before the current IT leadership joined the company reinforced the urgency and elevated cybersecurity to an executive-level priority with a focus on protecting customer trust. The goal was to build a multi-layered security model that could deliver autonomous, enterprise-wide protection without adding headcount.

Managing cyber risk in M&A

Mergers and acquisitions are central to the grocery holding company’s growth strategy. But each transaction introduces new cyber risk, including inherited network architectures, inconsistent tooling, excessive privileges, and remnants of prior security incidents that were never fully remediated.

“Our M&A targets range from small chains with a single IT person and limited cyber tools to large chains with more developed IT teams, toolsets and instrumentation,” explains the VP of IT. “We needed a fast, repeatable, and reliable way to assess cyber risk before transactions closed.”

AI-driven security built for scale, speed, and resilience

Rather than layering additional point tools onto an already complex environment, the retailer adopted the Darktrace ActiveAI Security Platform™ in 2020 as part of a broader modernization effort to improve resilience, close visibility gaps, and establish a security foundation that could scale with growth.

“Darktrace’s AI-driven approach provided the ideal solution to these challenges,” shares the VP of IT. “It has empowered our organization to maintain a robust security strategy, ensuring the protection of our network and the smooth operation of our business.”

Enterprise-wide visibility into traffic  

By monitoring both north-south and east-west traffic and applying Self-Learning AI, Darktrace develops a dynamic understanding of how users and devices normally behave across locations, roles, and systems.

“Modeling normal behavior across the environment enables us to quickly spot behavior that doesn’t fit. Even subtle changes that could signal a threat but appear legitimate at first glance,” explains the VP of IT.

Real-time threat containment, 24/7

Adopting autonomous response has created operational breathing room for the security team, says the company’s Cybersecurity  Engineer.

“Early on, we enabled full Darktrace autonomous mode and we continue to do so today,” shares the IT Security Architect. “Allowing the technology to act first gives us the time we need to investigate incidents during business hours without putting the business at risk.”

Unified, actionable view of security ecosystem

The grocery retailer integrated Darktrace with its existing security ecosystem of firewalls, vulnerability management tools, and endpoint detection and response, and the VP of IT described the adoption process as “exceptionally smooth.”

The team can correlate enterprise-wide security data for a unified and actionable picture of all activity and risk. Using this “single pane of glass” approach, the retailer trains Level 1 and Level 2 operations staff to assist with investigations and user follow-ups, effectively extending the reach of the security function without expanding headcount.

From reactive defense to security at scale

With Darktrace delivering continuous visibility, autonomous containment, and integrated security workflows, the organization has strengthened its cybersecurity posture while improving operational efficiency. The result is a security model that not only reduces risk, but also supports growth, resilience, and informed decision-making at the business level.

Faster detection, faster resolution

With autonomous detection and response, the retailer can immediately contain risk while analysts investigate and validate activity. With this approach, the company can maintain continuous protection even outside business hours and reduce the chance of lateral spread across systems or locations.

Enterprise-grade protection with a lean team

From cloud environments to clients to SaaS collaboration tools, Darktrace provides holistic autonomous AI defense, processing petabytes of the organization’s network traffic and investigating millions of individual events that could be indicative of a wider incident.

Today, Darktrace autonomously conducts the majority of all investigations on behalf of the IT team, escalating only a tiny fraction for analyst review. The impact has been profound, freeing analysts from endless alerts and hours of triage so they can focus on more valuable, proactive, and gratifying work.

“From an operational perspective, Darktrace gives us time back,” says the Cybersecurity Engineer. More importantly, says the VP of IT, “it gives us peace of mind that we’re protected even if we’re not actively monitoring every alert.”

A strategic input for M&A decision-making

One of the most strategic outcomes has been the role of cybersecurity on M&A. 90 days prior to closing a transaction, the security team uses Darktrace alongside other tools to perform a cyber risk assessment of the potential acquisition. “Our approach with Darktrace has consistently identified gaps and exposed risks,” says the VP of IT, including:

  • Remnants of previous incidents that were never fully remediated
  • Network configurations with direct internet exposure
  • Excessive administrative privileges in Active Directory or on critical hosts

While security findings may not alter deal timelines, the VP of IT says they can have enormous business implications. “With early visibility into these risks, we can reduce exposure to inherited cyber threats, strengthen our position during negotiations, and establish clear remediation requirements.”

A security strategy built to evolve with the business

As the holding group expands its cloud footprint, it will extend Darktrace protections into Azure, applying the same AI-driven visibility and autonomous response to cloud workloads. The VP of IT says Darktrace's evolving capabilities will be instrumental in addressing the organization’s future cybersecurity needs and ability to adapt to the dynamic nature of cloud security.

“With Darktrace’s AI-driven approach, we have moved beyond reactive defense, establishing a resilient security foundation for confident expansion and modernization.”

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