Cyber risk and advisory programs that identify security gaps and build strategies to address them.
MDR that provides improved detection, 24/7 threat hunting, end-to-end coverage and most of all, complete Response.
Our team delivers the fastest response time in the industry. Threat suppression within just 4 hours of being engaged.
Visibility and response across your entire Microsoft security ecosystem.
XDR with Machine Learning that eliminates noise, enables real-time detection and response, and automatically blocks threats.
Be protected by the best from Day 1.
24/7 Threat Investigation and Response.
Expert threat hunting, original research, and proactive threat intelligence.
TRU is foundational to our MDR service. No add-ons or additional costs required.
Flexible MDR packages that enhance your cyber resilience and security operations.
Stop ransomware attacks before they disrupt your business.
Detect and respond to zero-day exploits.
Protect against third-party and supply chain risk.
Adopt a risk-based approach to cybersecurity.
Protect your most sensitive data.
Meet cybersecurity regulatory compliance mandates.
Eliminate misconfigurations and policy violations.
Prevent business disruption by outsourcing MDR.
Meet insurability requirements with MDR.
Defend brute force attacks, active intrusions and unauthorized scans.
Safeguard endpoints 24/7 by isolating and mediating threats to prevent lateral spread.
Enhance investigation and threat detection across multi-cloud or hybrid environments.
Remediate critical misconfigurations, security vulnerabilities and policy violations across cloud and containerized environments.
Detect malicious insider and identity-based behavior leveraging machine learning models.
THE THREAT eSentire is aware of widespread exploitation attempts targeting the recently disclosed ownCloud vulnerability CVE-2023-49103. CVE-2023-49103 (CVSS: 10) is tracked as a disclosure of… READ NOW
Our Threat Response Unit (TRU) publishes security advisories, blogs, reports, industry publications and webinars based on its original research and the insights driven through proactive threat hunts.
eSentire is The Authority in Managed Detection and Response Services, protecting the critical data and applications of 2000+ organizations in 80+ countries from known and unknown cyber threats. Founded in 2001, the company's mission is to hunt, investigate and stop cyber threats before they become business disrupting events.
Waterloo, ON and GITEX GLOBAL 2023, Dubai, UAE – October 18, 2023 – eSentire, Inc., the Authority in Managed Detection and Response (MDR), today announced that Inspira Enterprise Inc, (Inspira), a… READ NOW
We provide sophisticated cybersecurity solutions for Managed Security Service Providers (MSSPs), Managed Service Providers (MSPs), and Value-Added Resellers (VARs). Find out why you should partner with eSentire, the Authority in Managed Detection and Response, today.
We believe a multi-signal approach is paramount to protecting your complete attack surface. See why eSentire MDR means multi-signal telemetry and complete response.
See how our 24/7 SOC Cyber Analysts and Elite Threat Hunters stop even the most advanced cyberattacks before they disrupt your business.
Choose the right mix of Managed Detection and Response, Exposure Management, and Incident Response services to strengthen your cyber resilience.
Try our interactive tools including the MITRE ATT&CK Tool, the SOC Pricing Calculator, the Cybersecurity Maturity Assessment, and our MDR ROI Calculator.
Read the latest security advisories, blogs, reports, industry publications and webinars published by eSentire's Threat Response Unit (TRU).
See why 2000+ organizations count on eSentire to build resilience and prevent business disruption.
TRU Positives: Weekly investigation summaries and recommendations from eSentire's Threat Response Unit (TRU)
BY eSentire Threat Response Unit (TRU)
March 9, 2023 | 7 MINS READ
Adversaries don’t work 9-5 and neither do we. At eSentire, our 24/7 SOCs are staffed with Elite Threat Hunters and Cyber Analysts who hunt, investigate, contain and respond to threats within minutes.
We have discovered some of the most dangerous threats and nation state attacks in our space – including the Kaseya MSP breach and the more_eggs malware.
Our Security Operations Centers are supported with Threat Intelligence, Tactical Threat Response and Advanced Threat Analytics driven by our Threat Response Unit – the TRU team.
In TRU Positives, eSentire’s Threat Response Unit (TRU) provides a summary of a recent threat investigation. We outline how we responded to the confirmed threat and what recommendations we have going forward.
Here’s the latest from our TRU Team…
In December, we published a summary of BatLoader activity whereby Google Search Ads were used to impersonate software such as WinRAR to deliver malicious Windows Installer files. The installer files contained custom action commands which used PowerShell to download and execute payloads (Redline Stealer, Ursnif, etc.) hosted on legitimate websites.
Throughout February 2023, TRU has observed a series of newly registered websites impersonating various applications and brands. Included among these are:
In addition to comparable domain registration attributes, these websites tend to follow a similar naming convention where one or more characters are appended to the impersonated brand name (e.g., adobe-l[.]com vs adobe.com). These sites were used to host imposter download pages and all likely stem from malicious advertisements on Google Search Ads. A more complete list can be found at the end of this post.
BatLoader continues to see changes and improvement since it first emerged in 2022. Recent samples analyzed by TRU utilize Windows Installer files masquerading as the above applications to launch embedded Python scripts.
In mid-February 2023, eSentire MDR for Endpoint blocked an attempt to execute Ursnif via code injection on a manufacturing customer’s endpoint. A subsequent investigation traced the infection to a Google search result for Adobe Reader by the victim user.
The user had clicked on a top-of-page ad on the search results page where they were directed via an intermediary website (adolbe[.]website) to adobe-e[.]com, a webpage masquerading as Adobe Acrobat Reader (Figure 1). As a result, the user unknowingly downloaded and executed AdobeSetup.msi(9ebbe0a1b79e6f13bfca014f878ddeec), BatLoader’s Windows Installer file.
Like previous versions of BatLoader, the MSI file contains Custom Actions to execute commands. In this case, the command executed an embedded batch file (seen here as InstallPython.bat, also observed as PythonFramework.bat) with admin privileges in a hidden window.
A decoy application was written to C:\Program Files (x86)\Chat Mapper along with BatLoader scripts and supporting files (Figure 2).
The batch file (figure 3, insert) performs the following actions:
In this case, two Python files (framework.py and frameworkb.py) were included in the package. These were protected using PyArmor and require unpacking with tools such as PyArmor-Unpacker (Figure 4). The files use a script copied from a Stack Overflow question as a template for executing Python code with elevated privileges.
BatLoader’s instruction set is inserted into the main function of the Stack Overflow Python script. The code retrieves an encrypted payload as control.exe.enc then executes a series of Windows commands. The instructions executed by both Python files were nearly identical except for a change in the payload URL.
The commands shown in Figure 5 are summarized as follows:
In the above-mentioned case, the payload intercepted by MDR for Endpoint was Ursnif (md5hash 0cb75b1192b23b8e03d955f1156ad19e), specifically isfb_v2.14+ variant configured to connect to the following C2 domains:
Ursnif’s persistence was achieved using a registry run key (VirtualStop) under HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run. This value executed a shortcut (LineType.lnk) which in turn launches a PowerShell script (CharReturn.ps1), as seen in Figure 6.
CharReturn.ps1 executed a staged PowerShell loader from registry at HKEY_USERS\Software\AppDataLow\Software\Microsoft\[randomstring]. The loader contained the embedded Ursnif binary which is injected into the Explorer process.
In this incident, MDR for Endpoint identified and blocked PowerShell execution of the Ursnif loader stored in registry.
Observed URL structures would suggest multiple payloads are available for download:
BatLoader has historically been linked to payloads such as Redline Stealer, SystemBC RAT, Syncro RMM, Vidar Stealer, Ursnif and Cobalt Strike. Analysis of more recent samples in March 2023 has yielded both Vidar Stealer and Ursnif trojans.
TRU has reviewed samples from public malware repositories which exhibited slightly different behavior than what was seen in the February incident described above. This sample from mid-February contained a third Python file named ‘networkframework.py’:
Like the others, it is obfuscated with PyArmor and contains an identical series of commands to handle payload retrieval, decryption and execution via WorkFolder.exe. In addition, netframework.py contains checks for curating payloads for domain-joined systems with more than 2 IP neighbors in the system’s ARP table.
This behavior has been previously observed whereby BatLoader executed Cobalt Strike in addition to the standard payloads such as Ursnif or Vidar. We assess this is done to prep systems residing in business networks for further infiltration.
As of time of writing, the payload URLs were no longer available for retrieval, but given that this fits into BatLoader’s known historical target selection patterns, we assess that Cobalt Strike is the probable candidate.
Suspected BatLoader Domains Registered in February 2023:
eSentire’s Threat Response Unit (TRU) is a world-class team of threat researchers who develop new detections enriched by original threat intelligence and leverage new machine learning models that correlate multi-signal data and automate rapid response to advanced threats.
If you are not currently engaged with an MDR provider, eSentire MDR can help you reclaim the advantage and put your business ahead of disruption.
Learn what it means to have an elite team of Threat Hunters and Researchers that works for you. Connect with an eSentire Security Specialist.
The eSentire Threat Response Unit (TRU) is an industry-leading threat research team committed to helping your organization become more resilient. TRU is an elite team of threat hunters and researchers that supports our 24/7 Security Operations Centers (SOCs), builds threat detection models across the eSentire XDR Cloud Platform, and works as an extension of your security team to continuously improve our Managed Detection and Response service. By providing complete visibility across your attack surface and performing global threat sweeps and proactive hypothesis-driven threat hunts augmented by original threat research, we are laser-focused on defending your organization against known and unknown threats.