Uncover New Malicious Email Payloads in Google Translate
Discover how threat actors are concealing malicious email payloads within Google Translate domains. Learn how Darktrace responds to these attacks effectively.
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
Rachel Resnekov
Cyber Analyst
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03
Nov 2022
Darktrace recently detected a new technique used by threat actors to deliver malicious email payloads. The malicious link was observed hidden within a legitimate domain, namely Google Translate services. To understand its abusive capabilities, it is important to first understand a benign case of how these links are created.
Google often provides a ‘Translate this page’ option for sites written in a different language to the default browser language.
Figure 1: A google search result for an international company E.g ‘Crédit Agricole’ gives the option to translate the page from French to English.
Figure 2: When clicked, the browser displays a link with a translate[.]goog domain, and the original domain, credit-agricole[.]fr, becomes the link’s subdomain.
When this feature is exploited by threat actors it can be particularly dangerous, as legacy security products that rely on ‘known’ or ‘safe’ domain-based detection are likely to register these emails as safe and provide no protective actions. If a recipient were to click on the malicious link, they could risk losing their credentials or even compromising their machine.
In contrast, Darktrace/Email has been able to consistently identify and action emails from such campaigns. This blog will discuss one of these events.
The Campaign
The apparent motive in this attack was to harvest credentials and/or deploy malware on the recipient’s device. Credential harvesting can lead to the sale of credentials on the dark web, or the attacker may choose to leverage those credentials in subsequent attacks. Both harvesting credentials and deploying malware have severe potential ramifications, including but not limited to sensitive company data leaks and financial loss.
During this attack, the threat actor sent similar emails to a group of recipients in a short space of time. The recipients were not normally associated with each other and Darktrace swiftly identified them as unsolicited bulk mail. The new technique that was leveraged included using Google’s translate services to share malicious links using legitimate seeming domains. The malicious host was visible within the subdomain ‘636416-selcdn-ru[.]translate[.]goog’.
When clicked, the link displays a google translate page stating, “Can’t translate this page”. There is then a hyperlink, “Go to original page”, that brings the user to the malicious host- 636416[.]selcdn[.]ru. Finally, the host displays a fake webmail portal login. If a user engages, the attacker can harvest their credentials to either sell or use in subsequent attacks.
Figure 3- The Google Translate page that is displayed once clicking on the full link within the email. The hyperlink at the bottom of the image is where the user is redirected by clicking “Go to original page”. It is there that the fake webmail portal login is then displayed.
Darktrace Coverage
As the malicious emails contained links to ‘safe’ Google Translate domains, most email security products would not characterize the links as suspicious. However, Darktrace/Email levies hundreds of metrics to identify whether emails belong in a recipient’s inbox. In this case Darktrace highlighted anomalies including rare subdomains, links containing unknown redirects, emails from spoofed freemail accounts and senders that had sent a relatively large number of emails within a short time frame. Furthermore, the attacker had never sent any previous emails to the organization prior to this email campaign.
On top of providing visibility, the RESPOND function of Darktrace/Email took action autonomously and instantaneously without any human confirmation required. These actions included locking links and holding malicious emails.
Figure 4- Darktrace/Email overview tab shows the Anomaly Indicators section as well as the History, Association, and Validation information of this sender.
Figure 5 - The Darktrace RESPOND/Email model tab displays all models that triggered on the email and the associated actions. The most severe delivery action supersedes the others, so here the email was held.
Concluding Thoughts
Threat actors are continuously updating the way they deliver malicious payloads within emails. While this particular email campaign utilized Google Translate domains to hide malicious links, subsequent attacks may well be seen leveraging other legitimate domains. Companies are only as strong as their weakest link; a single compromised internal email account can be used to send phishing emails to internal recipients, collect sensitive company information, inject malware onto the device, and more. Security tools must evolve to focus on anomalies within the email, rather than relying on rules or signatures of previously seen attacks. Furthermore, email tools must be able to autonomously respond as soon as the malicious emails enter the company’s environment. Only with these precautions will the risks associated with malicious emails be mitigated.
Thanks to Steven Haworth and Steven Sosa for their contributions.
Appendices
Relevant Darktrace Model Detections
· Association / Anomalous Association
· Association / New Sender
· Association / Unknown Sender
· Association / Unlikely Recipient Association
· High Antigena Anomaly [part of the RESPOND functionality]
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.
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Catching a RAT: How Darktrace neutralized AsyncRAT
What is a RAT?
As the proliferation of new and more advanced cyber threats continues, the Remote Access Trojan (RAT) remains a classic tool in a threat actor's arsenal. RATs, whether standardized or custom-built, enable attackers to remotely control compromised devices, facilitating a range of malicious activities.
What is AsyncRAT?
Since its first appearance in 2019, AsyncRAT has become increasingly popular among a wide range of threat actors, including cybercriminals and advanced persistent threat (APT) groups.
Originally available on GitHub as a legitimate tool, its open-source nature has led to widespread exploitation. AsyncRAT has been used in numerous campaigns, including prolonged attacks on essential US infrastructure, and has even reportedly penetrated the Chinese cybercriminal underground market [1] [2].
How does AsyncRAT work?
Original source code analysis of AsyncRAT demonstrates that once installed, it establishes persistence via techniques such as creating scheduled tasks or registry keys and uses SeDebugPrivilege to gain elevated privileges [3].
Its key features include:
Keylogging
File search
Remote audio and camera access
Exfiltration techniques
Staging for final payload delivery
These are generally typical functions found in traditional RATs. However, it also boasts interesting anti-detection capabilities. Due to the popularity of Virtual Machines (VM) and sandboxes for dynamic analysis, this RAT checks for the manufacturer via the WMI query 'Select * from Win32_ComputerSystem' and looks for strings containing 'VMware' and 'VirtualBox' [4].
Darktrace’s coverage of AsyncRAT
In late 2024 and early 2025, Darktrace observed a spike in AsyncRAT activity across various customer environments. Multiple indicators of post-compromise were detected, including devices attempting or successfully connecting to endpoints associated with AsyncRAT.
On several occasions, Darktrace identified a clear association with AsyncRAT through the digital certificates of the highlighted SSL endpoints. Darktrace’s Real-time Detection effectively identified and alerted on suspicious activities related to AsyncRAT. In one notable incident, Darktrace’s Autonomous Response promptly took action to contain the emerging threat posed by AsyncRAT.
AsyncRAT attack overview
On December 20, 2024, Darktrace first identified the use of AsyncRAT, noting a device successfully establishing SSL connections to the uncommon external IP 185.49.126[.]50 (AS199654 Oxide Group Limited) via port 6606. The IP address appears to be associated with AsyncRAT as flagged by open-source intelligence (OSINT) sources [5]. This activity triggered the device to alert the ‘Anomalous Connection / Rare External SSL Self-Signed' model.
Figure 1: Model alert in Darktrace / NETWORK showing the repeated SSL connections to a rare external Self-Signed endpoint, 185.49.126[.]50.
Following these initial connections, the device was observed making a significantly higher number of connections to the same endpoint 185.49.126[.]50 via port 6606 over an extended period. This pattern suggested beaconing activity and triggered the 'Compromise/Beaconing Activity to External Rare' model alert.
Further analysis of the original source code, available publicly, outlines the default ports used by AsyncRAT clients for command-and-control (C2) communications [6]. It reveals that port 6606 is the default port for creating a new AsyncRAT client. Darktrace identified both the Certificate Issuer and the Certificate Subject as "CN=AsyncRAT Server". This SSL certificate encrypts the packets between the compromised system and the server. These indicators of compromise (IoCs) detected by Darktrace further suggest that the device was successfully connecting to a server associated with AsyncRAT.
Figure 2: Model alert in Darktrace / NETWORK displaying the Digital Certificate attributes, IP address and port number associated with AsyncRAT.
Figure 3: Darktrace’s detection of repeated connections to the suspicious IP address 185.49.126[.]50 over port 6606, indicative of beaconing behavior.
Figure 4: Darktrace's Autonomous Response actions blocking the suspicious IP address,185.49.126[.]50.
A few days later, the same device was detected making numerous connections to a different IP address, 195.26.255[.]81 (AS40021 NL-811-40021), via various ports including 2106, 6606, 7707, and 8808. Notably, ports 7707 and 8808 are also default ports specified in the original AsyncRAT source code [6].
Figure 5: Darktrace’s detection of connections to the suspicious endpoint 195.26.255[.]81, where the default ports (6606, 7707, and 8808) for AsyncRAT were observed.
Similar to the activity observed with the first endpoint, 185.49.126[.]50, the Certificate Issuer for the connections to 195.26.255[.]81 was identified as "CN=AsyncRAT Server". Further OSINT investigation confirmed associations between the IP address 195.26.255[.]81 and AsyncRAT [7].
Figure 6: Darktrace's detection of a connection to the suspicious IP address 195.26.255[.]81 and the domain name identified under the common name (CN) of a certificate as AsyncRAT Server.
Once again, Darktrace's Autonomous Response acted swiftly, blocking the connections to 195.26.255[.]81 throughout the observed AsyncRAT activity.
Figure 7: Darktrace's Autonomous Response actions were applied against the suspicious IP address 195.26.255[.]81.
A day later, Darktrace again alerted to further suspicious activity from the device. This time, connections to the suspicious endpoint 'kashuub[.]com' and IP address 191.96.207[.]246 via port 8041 were observed. Further analysis of port 8041 suggests it is commonly associated with ScreenConnect or Xcorpeon ASIC Carrier Ethernet Transport [8]. ScreenConnect has been observed in recent campaign’s where AsyncRAT has been utilized [9]. Additionally, one of the ASN’s observed, namely ‘ASN Oxide Group Limited’, was seen in both connections to kashuub[.]com and 185.49.126[.]50.
This could suggest a parallel between the two endpoints, indicating they might be hosting AsyncRAT C2 servers, as inferred from our previous analysis of the endpoint 185.49.126[.]50 and its association with AsyncRAT [5]. OSINT reporting suggests that the “kashuub[.]com” endpoint may be associated with ScreenConnect scam domains, further supporting the assumption that the endpoint could be a C2 server.
Darktrace’s Autonomous Response technology was once again able to support the customer here, blocking connections to “kashuub[.]com”. Ultimately, this intervention halted the compromise and prevented the attack from escalating or any sensitive data from being exfiltrated from the customer’s network into the hands of the threat actors.
Figure 8: Darktrace’s Autonomous Response applied a total of nine actions against the IP address 191.96.207[.]246 and the domain 'kashuub[.]com', successfully blocking the connections.
Due to the popularity of this RAT, it is difficult to determine the motive behind the attack; however, from existing knowledge of what the RAT does, we can assume accessing and exfiltrating sensitive customer data may have been a factor.
Conclusion
While some cybercriminals seek stability and simplicity, openly available RATs like AsyncRAT provide the infrastructure and open the door for even the most amateur threat actors to compromise sensitive networks. As the cyber landscape continually shifts, RATs are now being used in all types of attacks.
Darktrace’s suite of AI-driven tools provides organizations with the infrastructure to achieve complete visibility and control over emerging threats within their network environment. Although AsyncRAT’s lack of concealment allowed Darktrace to quickly detect the developing threat and alert on unusual behaviors, it was ultimately Darktrace Autonomous Response's consistent blocking of suspicious connections that prevented a more disruptive attack.
Credit to Isabel Evans (Cyber Analyst), Priya Thapa (Cyber Analyst) and Ryan Traill (Analyst Content Lead)
Appendices
Real-time Detection Models
Compromise / Suspicious SSL Activity
Compromise / Beaconing Activity To External Rare
Compromise / High Volume of Connections with Beacon Score
Anomalous Connection / Suspicious Self-Signed SSL
Compromise / Sustained SSL or HTTP Increase
Compromise / SSL Beaconing to Rare Destination
Compromise / Suspicious Beaconing Behaviour
Compromise / Large Number of Suspicious Failed Connections
Autonomous Response Models
Antigena / Network / Significant Anomaly / Antigena Controlled and Model Alert
Revolutionizing OT Risk Prioritization with Darktrace 6.3
Powering smarter protection for industrial systems
In industrial environments, security challenges are deeply operational. Whether you’re running a manufacturing line, a power grid, or a semiconductor fabrication facility (fab), you need to know: What risks can truly disrupt my operations, and what should I focus on first?
Teams need the right tools to shift from reactive defense, constantly putting out fires, to proactively thinking about their security posture. However, most OT teams are stuck using IT-centric tools that don’t speak the language of industrial systems, are consistently overwhelmed with static CVE lists, and offer no understanding of OT-specific protocols. The result? Compliance gaps, siloed insights, and risk models that don’t reflect real-world exposure, making risk prioritization seem like a luxury.
Darktrace / OT 6.3 was built in direct response to these challenges. Developed in close collaboration with OT operators and engineers, this release introduces powerful upgrades that deliver the context, visibility, and automation security teams need, without adding complexity. It’s everything OT defenders need to protect critical operations in one platform that understands the language of industrial systems.
Contextual risk modeling with smarter Risk Scoring
Darktrace / OT 6.3 introduces major upgrades to OT Risk Management, helping teams move beyond generic CVE lists with AI-driven risk scoring and attack path modeling.
By factoring in real-world exploitability, asset criticality, and operational context, this release delivers a more accurate view of what truly puts critical systems at risk.
The platform now integrates:
CISA’s Known Exploited Vulnerabilities (KEV) database
End-of-life status for legacy OT devices
Firewall misconfiguration analysis
Incident response plan alignment
Most OT environments are flooded with vulnerability data that lacks context. CVE scores often misrepresent risk by ignoring how threats move through the environment or whether assets are even reachable. Firewalls are frequently misconfigured or undocumented, and EOL (End of Life) devices, some of the most vulnerable, often go untracked.
Legacy tools treat these inputs in isolation. Darktrace unifies them, showing teams exactly which attack paths adversaries could exploit, mapped to the MITRE ATT&CK framework, with visibility into where legacy tech increases exposure.
The result: teams can finally focus on the risks that matter most to uptime, safety, and resilience without wasting resources on noise.
Automating compliance with dynamic IEC-62443 reporting
Darktrace / OT now includes a purpose-built IEC-62443-3-3 compliance module, giving industrial teams real-time visibility into their alignment with regulatory standards. No spreadsheets required!
Industrial environments are among the most heavily regulated. However, for many OT teams, staying compliant is still a manual, time-consuming process.
Darktrace / OT introduces a dedicated IEC-62443-3-3 module designed specifically for industrial environments. Security and operations teams can now map their security posture to IEC standards in real time, directly within the platform. The module automatically gathers evidence across all four security levels, flags non-compliance, and generates structured reports to support audit preparation, all in just a few clicks.Most organizations rely on spreadsheets or static tools to track compliance, without clear visibility into which controls meet standards like IEC-62443. The result is hidden gaps, resource-heavy audits, and slow remediation cycles.
Even dedicated compliance tools are often built for IT, require complex setup, and overlook the unique devices found in OT environments. This leaves teams stuck with fragmented reporting and limited assurance that their controls are actually aligned with regulatory expectations.
By automating compliance tracking, surfacing what matters most, and being purpose built for industrial environments, Darktrace / OT empowers organizations to reduce audit fatigue, eliminate blind spots, and focus resources where they’re needed most.
Expanding protocol visibility with deep insights for specialized OT operations
Darktrace has expanded its Deep Packet Inspection (DPI) capabilities to support five industry-specific protocols, across healthcare, semiconductor manufacturing, and ABB control systems.
The new protocols build on existing capabilities across all OT industry verticals and protocol types to ensure the Darktrace Self-Learning AI TM can learn intelligently about even more assets in complex industrial environments. By enabling native, AI-driven inspection of these protocols, Darktrace can identify both security threats and operational issues without relying on additional appliances or complex integrations.
Most security platforms lack native support for industry-specific protocols, creating critical visibility gaps in customer environments like healthcare, semiconductor manufacturing, and ABB-heavy industrial automation. Without deep protocol awareness, organizations struggle to accurately identify specialized OT and IoT assets, detect malicious activity concealed within proprietary protocol traffic, and generate reliable device risk profiles due to insufficient telemetry.
These blind spots result in incomplete asset inventories, and ultimately, flawed risk posture assessments which over-index for CVE patching and legacy equipment.
By combining protocol-aware detection with full-stack visibility across IT, OT, and IoT, Darktrace’s AI can correlate anomalies across domains. For example, connecting an anomaly from a Medical IoT (MIoT) device with suspicious behavior in IT systems, providing actionable, contextual insights other solutions often miss.
Conclusion
Together, these capabilities take OT security beyond alert noise and basic CVE matching, delivering continuous compliance, protocol-aware visibility, and actionable, prioritized risk insights, all inside a single, unified platform built for the realities of industrial environments.
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![Model alert in Darktrace / NETWORK showing the repeated SSL connections to a rare external Self-Signed endpoint, 185.49.126[.]50.](https://cdn.prod.website-files.com/626ff4d25aca2edf4325ff97/6823ad5f8454ff831da3182a_Screenshot%202025-05-13%20at%201.35.56%E2%80%AFPM.avif)
![Darktrace’s detection of repeated connections to the suspicious IP address 185.49.126[.]50 over port 6606, indicative of beaconing behavior.](https://cdn.prod.website-files.com/626ff4d25aca2edf4325ff97/6823adc5ac5c997938babf30_Screenshot%202025-05-13%20at%201.38.15%E2%80%AFPM.avif)
![Darktrace's Autonomous Response actions blocking the suspicious IP address,185.49.126[.]50.](https://cdn.prod.website-files.com/626ff4d25aca2edf4325ff97/6825268603a7a2b1459c9fea_Figure%204.avif)
![Darktrace’s detection of connections to the suspicious endpoint 195.26.255[.]81, where the default ports (6606, 7707, and 8808) for AsyncRAT were observed.](https://cdn.prod.website-files.com/626ff4d25aca2edf4325ff97/6823ae6e325a742b23ef6e6d_Screenshot%202025-05-13%20at%201.41.09%E2%80%AFPM.avif)
![Darktrace's detection of a connection to the suspicious IP address 195.26.255[.]81 and the domain name identified under the common name (CN) of a certificate as AsyncRAT Server](https://cdn.prod.website-files.com/626ff4d25aca2edf4325ff97/6823aea233fc6374c1432604_Screenshot%202025-05-13%20at%201.42.00%E2%80%AFPM.avif)
![Darktrace’s Autonomous Response applied a total of nine actions against the IP address 191.96.207[.]246 and the domain 'kashuub[.]com', successfully blocking the connections.](https://cdn.prod.website-files.com/626ff4d25aca2edf4325ff97/6823af1b3cbc7734f47fc15b_Screenshot%202025-05-13%20at%201.43.56%E2%80%AFPM.avif)
