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November 29, 2022

How to Cut Through Cyber Security Noise

Learn how Cyber AI Analyst tackles alert fatigue by categorizing vast amounts of data into actionable security incidents for your team's review.
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
Dan Fein
VP, Product
Written by
Elliot Stocker
Product SME
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29
Nov 2022

For cyber security experts, it’s hard enough staying on top of the latest threats and emerging attacks without having to deal with a virtual tsunami of alert noise from systems monitoring email, SaaS environments, and endpoints – in addition to IaaS cloud and on-premises networks. Unfortunately, fatigue from these demands can lead to overworking, burnout, and crucially, high employee turnover. 

The worldwide industry shortage of 3.5 million cyber security professionals only exacerbates the problem. Not only does it add pressure to the current stock of skilled and available security professionals, but it also raises the stakes for CISOs and other security leaders to find a way to cut through the alert noise while staying on ahead of threat actors who never stop innovating and applying novel malware strains and attack techniques.

Working Smarter Not Harder

One way to help with retention is to empower security teams to break away from monotony and to think creatively and leverage their expertise where it can really add value. Working smarter, rather than harder, is often easier said than done, but by employing automation and AI-driven tools to take on the heavy lifting of threat detection, investigation, and response, human teams can be given the breathing room needed to focus on long-term objectives and think more deeply about their security approaches.

It is important for security programs to continuously level up alongside evolving threat landscapes by questioning existing security operations, and this cannot be achieved during times of hand-to-hand alert combat.

When alerts are fewer, higher quality, and context-heavy, the background to each can be easily explored, whether that’s reevaluating a policy or configuration, or simply asking useful questions around the company’s broader security approach. Work done at this level empowers security teams and fosters growth.

Less is More

Business risk– or the potential impact of cyber disruption– should be the number one concern driving a security team, but lack of resources is a near-constant constraint. Reducing the volume of alerts doesn’t just mean bringing the noise floor up. You can think of the noise floor as an alert threshold: if it is too high then there are fewer alerts, but more threats may be missed, whereas if it is too low, there are high volumes of unhelpful false positives. Freeing up time for the team must not equate to ignoring alerts; it should instead mean focusing on the alerts that matter.

Darktrace’s technologies make this possible, with Darktrace DETECT™ and Cyber AI Analyst working together to address alert fatigue and burnout for security teams while strengthening an organizations’ overall security posture. Cyber AI Analyst essentially takes over the busy work from the human analysts and elevates a team’s overall decision making. Teams now operate at higher levels, as they’re not stuck in mundane alert management and humans are brought in only after the machine and AI have done the heavy lifting.

“Before AI Analyst, we were barely treading water with all of the alerts, most of which were false positives, our old systems produced daily. With AI Analyst, we’ve been able to exponentially reduce those alerts, harden our environment, and get strategic.”

Dr. Robert Spangler, the CISO and Assistant Executive Director of the New Jersey State Bar Association.

Figure 1: Billions of individual events are reduced into a critical incident for review


Imagine a scenario in which Darktrace observed around 9.6 billion events over a 28-day period. DETECT and Cyber AI Analyst might distill that huge amount of data down into just, say, 54 critical incidents, or just two per day. Here’s how:

9.6 billion events

When trying to understand the full picture, every single puzzle piece counts. That’s why Darktrace’s Self-Learning AI goes wherever your organization has data, integrating with data sources across the digital estate, including network, email, endpoints, OT, cloud, and SaaS environments. And with an open architecture, Darktrace facilitates quick and easy integrations with everything from SIEMs and SOARs to public clouds and the latest Zero Trust technologies. So, any data can become learnable, whether directly ingested or via integration.

By examining this full and contextualized data set, Self-Learning AI builds a constantly evolving understanding of what ‘normal’ looks like for the entire organization. Every connection, every email, app login, resource accessed, VM spun up, PLC reprogrammed, and more become signals from which Darktrace can learn, evaluate, and improve its understanding.

40,404 model breaches

The billions of events are analyzed by Darktrace DETECT, which uses its extensive knowledge of ‘normal’ to draw out hosts of subtle anomalies or ‘AI model breaches.’ Many of these AI model breaches will be weak indicators of threatening activity, and most will not be sufficient to individually signal a threat. For that reason, no human attention is required at this stage. Darktrace DETECT will continue to draw anomalous behaviors from the ongoing stream of events without the need for intervention. 

200 incidents

The Cyber AI Analyst takes the total list of model breaches collated by DETECT and performs the truly sophisticated work of determining distinct threat incidents. By piecing together anomalies which may, in themselves, appear harmless, the AI Analyst draws out subtle and often wide-ranging attacks, tracking their route from the initial compromise to the present moment. This creates a much shorter list of genuine threat incidents, but there is still no need for human attention at this stage.

54 critical incidents

Once it has discovered the threat incidents facing an organization, the Cyber AI Analyst begins the crucial processes of triage to determine which incidents need to be surfaced to the security team, and in what order of priority. This supplies the human team with a highly focused briefing of the most pressing threats, massively reducing their overall workload and minimizing or potentially eradicating alert fatigue. In the above example of a month with over 9.6 billion distinct events, the team are left with just two incidents to address per day. These two incidents are clearly presented with natural language-processing and all the most relevant info, including details, devices, and dates. 

“When we had other, noisier systems, we didn’t have the time to have truly in-depth discussions or conduct deep investigations, so there were fewer teachable moments for junior team members and fewer opportunities to inform our cybersecurity strategy as a whole,” Spangler said. “Now, we’re not just a better team, we’re more efficient, responsive, and informed than we’ve ever been. We’re all better cyber security professionals as a result.”

In the event of a breach, CISOs and security leaders want the full incident report, and they want it yesterday. The promise of AI is to handle specific tasks at a speed and scale that humans can’t. Going from 9.6 billion events to 54 incidents demonstrates the scale, but it’s important to consider the impact of speed here as well, as the Cyber AI Analyst works in real time, meaning all relevant events are presented in an easy to consume downloadable report available immediately upon investigation.

This isn’t a black box either; every step of the AI Analyst’s investigation process is visible to the human team. Not only can they see the relevant events and breaches that led to the incident, but if required, they can pivot into them easily with a click. If the investigation requires going all the way down to the metadata level to easily peruse the filtered events of the 9.6 billion overall signals or even to PCAP data, those are available and easy to find too.

Since DETECT and Cyber AI Analyst not only reduce alert fatigue but also simplify incident investigations, security teams feel empowered and experience less burnout. 

“We’ve been stable and have had minimal turnover since we started using AI Analyst,” Spangler said. “We’re not scrambling to keep up with noisy and time-consuming false positives, making the investigations that we undertake stimulating and– I say this cautiously– fun! Put simply, the thing we all love about this career, the virtual chess game we play with attackers, is a lot more fun when you know you’re going to win.”

Autonomous Response

Organizations that deploy Darktrace RESPOND™ can address the incidents raised by DETECT and the Cyber AI Analyst autonomously, and in mere seconds. Using the full context of the organization built up by Self-Learning AI, RESPOND takes the least disruptive measures necessary to disarm threats at machine speed. By the time the security team learns about the attack, it is already contained, continuing to save them from the hand-to-hand combat of threat fighting.

With day-to-day threat detection, response, and analysis taken care of, security teams are free to give full and sustained attention to their overall security posture. Neutralized threats may yet reveal broader security gaps and potential improvements which the team now has the time and headspace to pursue.

For example, discovering a trend that users are uploading potentially sensitive data via third-party file-sharing services might lead to a discussion about whether it should be company policy to block access to this service, reducing to zero the number of future alerts that would have been triggered by this behavior. Importantly, this wouldn’t be altering the aforementioned noise floor, but instead fundamentally altering security policies to align with the needs of the business, which could indirectly affect future alerting, as activities may subside.

As a result, practitioners find more value in their work, security teams efforts are optimized, and organizations are strengthened overall.

“We’re now focused on the items that AI Analyst alerts us to, which are always worth looking into because they either identify an activity that we need to get eyes on and/or provide us with insight into ways we can harden our network,” Spangler said. “The hardening that we’ve done has been incalculably beneficial– it’s one of the reasons we get fewer alerts, and it’s also protected us against a wide variety of threats.”

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
Dan Fein
VP, Product
Written by
Elliot Stocker
Product SME

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November 27, 2025

From Amazon to Louis Vuitton: How Darktrace Detects Black Friday Phishing Attacks

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Why Black Friday Drives a Surge in Phishing Attacks

In recent years, Black Friday has shifted from a single day of online retail sales and discounts to an extended ‘Black Friday Week’, often preceded by weeks of online hype. During this period, consumers are inundated with promotional emails and marketing campaigns as legitimate retailers compete for attention.

Unsurprisingly, this surge in legitimate communications creates an ideal environment for threat actors to launch targeted phishing campaigns designed to mimic legitimate retail emails. These campaigns often employ social engineering techniques that exploit urgency, exclusivity, and consumer trust in well-known brands, tactics designed to entice recipients into opening emails and clicking on malicious links.

Additionally, given the seasonal nature of Black Friday and the ever-changing habits of consumers, attackers adopt new tactics and register fresh domains each year, rather than reusing domains previously flagged as spam or phishing endpoints. While this may pose a challenge for traditional email security tools, it presents no such difficulty for Darktrace / EMAIL and its anomaly-based approach.

In the days and weeks leading up to ‘Black Friday’, Darktrace observed a spike in sophisticated phishing campaigns targeting consumers, demonstrating how attackers combine phycological manipulation with technical evasion to bypass basic security checks during this high-traffic period. This blog showcases several notable examples of highly convincing phishing emails detected and contained by Darktrace / EMAIL in mid to late November 2025.

Darktrace’s Black Friday Detections

Brand Impersonation: Deal Watchdogs’ Amazon Deals

The impersonation major online retailers has become a common tactic in retail-focused attacks, none more so than Amazon, which ranked as the fourth most impersonated brand in 2024, only behind Microsoft, Apple, Google, and Facebook [1]. Darktrace’s own research found Amazon to be the most mimicked brand, making up 80% of phishing attacks in its analysis of global consumer brands.

When faced with an email that appears to come from a trusted sender like Amazon, recipients are far more likely to engage, increasing the success rate of these phishing campaigns.

In one case observed on November 16, Darktrace detected an email with the subject line “NOW LIVE: Amazon’s Best Early Black Friday Deals on Gadgets Under $60”. The email was sent to a customer by the sender ‘Deal Watchdogs’, in what appeared to be an attempt to masquerade as a legitimate discount-finding platform. No evidence indicated that the company was legitimate. In fact, the threat actor made no attempt to create a convincing name, and the domain appeared to be generated by a domain generation algorithm (DGA), as shown in Figure 2.

Although the email was sent by ‘Deal Watchdogs’, it attempted to impersonate Amazon by featuring realistic branding, including the Amazon logo and a shade of orange similar to that used by them for the ‘CLICK HERE’ button and headline text.

Figure 1: The contents of the email observed by Darktrace, featuring authentic-looking Amazon branding.

Darktrace identified that the email, marked as urgent by the sender, contained a suspicious link to a Google storage endpoint (storage.googleapis[.]com), which had been hidden by the text “CLICK HERE”. If clicked, the link could have led to a credential harvester or served as a delivery vector for a malicious payload hosted on the Google storage platform.

Fortunately, Darktrace immediately identified the suspicious nature of this email and held it before delivery, preventing recipients from ever receiving or interacting with the malicious content.

Figure 2: Darktrace / EMAIL’s detection of the malicious phishing email sent to a customer.

Around the same time, Darktrace detected a similar email attempting to spoof Amazon on another customer’s network with the subject line “Our 10 Favorite Deals on Amazon That Started Today”, also sent by ‘Deal Watchdogs,’ suggesting a broader campaign.

Analysis revealed that this email originated from the domain petplatz[.]com, a fake marketing domain previously linked to spam activity according to open-source intelligence (OSINT) [2].

Brand Impersonation: Louis Vuitton

A few days later, on November 20, Darktrace / EMAIL detected a phishing email attempting to impersonate the luxury fashion brand Louis Vuitton. At first glance, the email, sent under the name ‘Louis Vuitton’ and titled “[Black Friday 2025] Discover Your New Favorite Louis Vuitton Bag – Elegance Starts Here”, appeared to be a legitimate Black Friday promotion. However, Darktrace’s analysis uncovered several red flags indicating a elaborate brand impersonation attempt.

The email was not sent by Louis Vuitton but by rskkqxyu@bookaaatop[.]ru, a Russia-based domain never before observed on the customer’s network. Darktrace flagged this as suspicious, noting that .ru domains were highly unusual for this recipient’s environment, further reinforcing the likelihood of malicious intent. Subsequent analysis revealed that the domain had only recently registered and was flagged as malicious by multiple OSINT sources [3].

Figure 3: Darktrace / EMAIL’s detection of the malicious email attempting to spoofLouis Vuitton, originating from a suspicious Russia-based domain.

Darktrace further noted that the email contained a highly suspicious link hidden behind the text “View Collection” and “Unsubscribe,” ensuring that any interaction, whether visiting the supposed ‘handbag store’ or attempting to opt out of marketing emails, would direct recipients to the same endpoint. The link resolved to xn--80aaae9btead2a[.]xn--p1ai (топааабоок[.]рф), a domain confirmed as malicious by multiple OSINT sources [4]. At the time of analysis, the domain was inaccessible, likely due to takedown efforts or the short-lived nature of the campaign.

Darktrace / EMAIL blocked this email before it reached customer inboxes, preventing recipients from interacting with the malicious content and averting any disruption.

Figure 4: The suspicious domain linked in the Louis Vuitton phishing email, now defunct.

Too good to be true?

Aside from spoofing well-known brands, threat actors frequently lure consumers with “too good to be true” luxury offers, a trend Darktrace observed in multiple cases throughout November.

In one instance, Darktrace identified an email with the subject line “[Black Friday 2025] Luxury Watches Starting at $250.” Emails contained a malicious phishing link, hidden behind text like “Rolex Starting from $250”, “Shop Now”, and “Unsubscribe”.

Figure 5: Example of a phishing email detected by Darktrace, containing malicious links concealed behind seemingly innocuous text.

Similarly to the Louis Vuitton email campaign described above, this malicious link led to a .ru domain (hxxps://x.wwwtopsalebooks[.]ru/.../d65fg4er[.]html), which had been flagged as malicious by multiple sources [5].

Figure 6: Darktrace / EMAIL’s detection of a malicious email promoting a fake luxury watch store, which was successfully held from recipient inboxes.

If accessed, this domain would redirect users to luxy-rox[.]com, a recently created domain (15 days old at the time of writing) that has also been flagged as malicious by OSINT sources [6]. When visited, the redirect domain displayed a convincing storefront advertising high-end watches at heavily discounted prices.

Figure 7: The fake storefront presented upon visiting the redirectdomain, luxy-rox[.]com.

Although the true intent of this domain could not be confirmed, it was likely a scam site or a credential-harvesting operation, as users were required to create an account to complete a purchase. As of the time or writing, the domain in no longer accessible .

This email illustrates a layered evasion tactic: attackers employed multiple domains, rapid domain registration, and concealed redirects to bypass detection. By leveraging luxury branding and urgency-driven discounts, the campaign sought to exploit seasonal shopping behaviors and entice victims into clicking.

Staying Protected During Seasonal Retail Scams

The investigation into these Black Friday-themed phishing emails highlights a clear trend: attackers are exploiting seasonal shopping events with highly convincing campaigns. Common tactics observed include brand impersonation (Amazon, Louis Vuitton, luxury watch brands), urgency-driven subject lines, and hidden malicious links often hosted on newly registered domains or cloud services.

These campaigns frequently use redirect chains, short-lived infrastructure, and psychological hooks like exclusivity and luxury appeal to bypass user scepticism and security filters. Organizations should remain vigilant during retail-heavy periods, reinforcing user awareness training, link inspection practices, and anomaly-based detection to mitigate these evolving threats.

Credit to Ryan Traill (Analyst Content Lead) and Owen Finn (Cyber Analyst)

Appendices

References

1.        https://keepnetlabs.com/blog/top-5-most-spoofed-brands-in-2024

2.        https://www.virustotal.com/gui/domain/petplatz.com

3.        https://www.virustotal.com/gui/domain/bookaaatop.ru

4.        https://www.virustotal.com/gui/domain/xn--80aaae9btead2a.xn--p1ai

5.        https://www.virustotal.com/gui/url/e2b868a74531cd779d8f4a0e1e610ec7f4efae7c29d8b8ab32c7a6740d770897?nocache=1

6.        https://www.virustotal.com/gui/domain/luxy-rox.com

Indicators of Compromise (IoCs)

IoC – Type – Description + Confidence

petplatz[.]com – Hostname – Spam domain

bookaaatop[.]ru – Hostname – Malicious Domain

xn--80aaae9btead2a[.]xn--p1ai (топааабоок[.]рф) – Hostname - Malicious Domain

hxxps://x.wwwtopsalebooks[.]ru/.../d65fg4er[.]html) – URL – Malicious Domain

luxy-rox[.]com – Hostname -  Malicious Domain

MITRE ATT&CK Mapping  

Tactic – Technique – Sub-Technique  

Initial Access - Phishing – (T1566)  

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Ryan Traill
Analyst Content Lead

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November 27, 2025

CastleLoader & CastleRAT: Behind TAG150’s Modular Malware Delivery System

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What is TAG-150?

TAG-150, a relatively new Malware-as-a-Service (MaaS) operator, has been active since March 2025, demonstrating rapid development and an expansive, evolving infrastructure designed to support its malicious operations. The group employs two custom malware families, CastleLoader and CastleRAT, to compromise target systems, with a primary focus on the United States [1]. TAG-150’s infrastructure included numerous victim-facing components, such as IP addresses and domains functioning as command-and-control (C2) servers associated with malware families like SecTopRAT and WarmCookie, in addition to CastleLoader and CastleRAT [2].

As of May 2025, CastleLoader alone had infected a reported 469 devices, underscoring the scale and sophistication of TAG-150’s campaign [1].

What are CastleLoader and CastleRAT?

CastleLoader is a loader malware, primarily designed to download and install additional malware, enabling chain infections across compromised systems [3]. TAG-150 employs a technique known as ClickFix, which uses deceptive domains that mimic document verification systems or browser update notifications to trick victims into executing malicious scripts. Furthermore, CastleLoader leverages fake GitHub repositories that impersonate legitimate tools as a distribution method, luring unsuspecting users into downloading and installing malware on their devices [4].

CastleRAT, meanwhile, is a remote access trojan (RAT) that serves as one of the primary payloads delivered by CastleLoader. Once deployed, CastleRAT grants attackers extensive control over the compromised system, enabling capabilities such as keylogging, screen capturing, and remote shell access.

TAG-150 leverages CastleLoader as its initial delivery mechanism, with CastleRAT acting as the main payload. This two-stage attack strategy enhances the resilience and effectiveness of their operations by separating the initial infection vector from the final payload deployment.

How are they deployed?

Castleloader uses code-obfuscation methods such as dead-code insertion and packing to hinder both static and dynamic analysis. After the payload is unpacked, it connects to its command-and-control server to retrieve and running additional, targeted components.

Its modular architecture enables it to function both as a delivery mechanism and a staging utility, allowing threat actors to decouple the initial infection from payload deployment. CastleLoader typically delivers its payloads as Portable Executables (PEs) containing embedded shellcode. This shellcode activates the loader’s core module, which then connects to the C2 server to retrieve and execute the next-stage malware.[6]

Following this, attackers deploy the ClickFix technique, impersonating legitimate software distribution platforms like Google Meet or browser update notifications. These deceptive sites trick victims into copying and executing PowerShell commands, thereby initiating the infection kill chain. [1]

When a user clicks on a spoofed Cloudflare “Verification Stepprompt, a background request is sent to a PHP script on the distribution domain (e.g., /s.php?an=0). The server’s response is then automatically copied to the user’s clipboard using the ‘unsecuredCopyToClipboard()’ function. [7].

The Python-based variant of CastleRAT, known as “PyNightShade,” has been engineered with stealth in mind, showing minimal detection across antivirus platforms [2]. As illustrated in Figure 1, PyNightShade communicates with the geolocation API service ip-api[.]com, demonstrating both request and response behavior

Packet Capture (PCAP) of PyNightShade, the Python-based variant of CastleRAT, communicating with the geolocation API service ip-api[.]com.
Figure 1: Packet Capture (PCAP) of PyNightShade, the Python-based variant of CastleRAT, communicating with the geolocation API service ip-api[.]com.

Darktrace Coverage

In mid-2025, Darktrace observed a range of anomalous activities across its customer base that appeared linked to CastleLoader, including the example below from a US based organization.

The activity began on June 26, when a device on the customer’s network was observed connecting to the IP address 173.44.141[.]89, a previously unseen IP for this network along with the use of multiple user agents, which was also rare for the user.  It was later determined that the IP address was a known indicator of compromise (IoC) associated with TAG-150’s CastleRAT and CastleLoader operations [2][5].

Figure 2: Darktrace’s detection of a device making unusual connections to the malicious endpoint 173.44.141[.]89.

The device was observed downloading two scripts from this endpoint, namely ‘/service/download/data_5x.bin’ and ‘/service/download/data_6x.bin’, which have both been linked to CastleLoader infections by open-source intelligence (OSINT) [8]. The archives contains embedded shellcode, which enables attackers to execute arbitrary code directly in memory, bypassing disk writes and making detection by endpoint detection and response (EDR) tools significantly more difficult [2].

 Darktrace’s detection of two scripts from the malicious endpoint.
Figure 3: Darktrace’s detection of two scripts from the malicious endpoint.

In addition to this, the affected device exhibited a high volume of internal connections to a broad range of endpoints, indicating potential scanning activity. Such behavior is often associated with reconnaissance efforts aimed at mapping internal infrastructure.

Darktrace / NETWORK correlated these behaviors and generated an Enhanced Monitoring model, a high-fidelity security model designed to detect activity consistent with the early stages of an attack. These high-priority models are continuously monitored and triaged by Darktrace’s Security Operations Center (SOC) as part of the Managed Threat Detection and Managed Detection & Response services, ensuring that subscribed customers are promptly alerted to emerging threats.

Darktrace detected an unusual ZIP file download alongside the anomalous script, followed by internal connectivity. This activity was correlated under an Enhanced Monitoring model.
Figure 4: Darktrace detected an unusual ZIP file download alongside the anomalous script, followed by internal connectivity. This activity was correlated under an Enhanced Monitoring model.

Darktrace Autonomous Response

Fortunately, Darktrace’s Autonomous Response capability was fully configured, enabling it to take immediate action against the offending device by blocking any further connections external to the malicious endpoint, 173.44.141[.]89. Additionally, Darktrace enforced a ‘group pattern of life’ on the device, restricting its behavior to match other devices in its peer group, ensuring it could not deviate from expected activity, while also blocking connections over 443, shutting down any unwanted internal scanning.

Figure 5: Actions performed by Darktrace’s Autonomous Response to contain the ongoing attack.

Conclusion

The rise of the MaaS ecosystem, coupled with attackers’ growing ability to customize tools and techniques for specific targets, is making intrusion prevention increasingly challenging for security teams. Many threat actors now leverage modular toolkits, dynamic infrastructure, and tailored payloads to evade static defenses and exploit even minor visibility gaps. In this instance, Darktrace demonstrated its capability to counter these evolving tactics by identifying early-stage attack chain behaviors such as network scanning and the initial infection attempt. Autonomous Response then blocked the CastleLoader IP delivering the malicious ZIP payload, halting the attack before escalation and protecting the organization from a potentially damaging multi-stage compromise

Credit to Ahmed Gardezi (Cyber Analyst) Tyler Rhea (Senior Cyber Analyst)
Edited by Ryan Traill (Analyst Content Lead)

Appendices

Darktrace Model Detections

  • Anomalous Connection / Unusual Internal Connections
  • Anomalous File / Zip or Gzip from Rare External Location
  • Anomalous File / Script from Rare External Location
  • Initial Attack Chain Activity (Enhanced Monitoring Model)

MITRE ATT&CK Mapping

  • T15588.001 - Resource Development – Malware
  • TG1599 – Defence Evasion – Network Boundary Bridging
  • T1046 – Discovery – Network Service Scanning
  • T1189 – Initial Access

List of IoCs
IoC - Type - Description + Confidence

  • 173.44.141[.]89 – IP – CastleLoader C2 Infrastructure
  • 173.44.141[.]89/service/download/data_5x.bin – URI – CastleLoader Script
  • 173.44.141[.]89/service/download/data_6x.bin – URI  - CastleLoader Script
  • wsc.zip – ZIP file – Possible Payload

References

[1] - https://blog.polyswarm.io/castleloader

[2] - https://www.recordedfuture.com/research/from-castleloader-to-castlerat-tag-150-advances-operations

[3] - https://www.pcrisk.com/removal-guides/34160-castleloader-malware

[4] - https://www.scworld.com/brief/malware-loader-castleloader-targets-devices-via-fake-github-clickfix-phishing

[5] https://www.virustotal.com/gui/ip-address/173.44.141.89/community

[6] https://thehackernews.com/2025/07/castleloader-malware-infects-469.html

[7] https://www.cryptika.com/new-castleloader-attack-using-cloudflare-themed-clickfix-technique-to-infect-windows-computers/

[8] https://www.cryptika.com/castlebot-malware-as-a-service-deploys-range-of-payloads-linked-to-ransomware-attacks/

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