Stray Cat, Open Doors: How k0t Wanders Through the Network Edge

Introduction

Group-IB Threat Intelligence, together with NyxLab, collaborated on a joint investigation on a campaign involving widespread exploitation of network edge devices. This joint-investigation effort has managed to uncover indications that this may be connected to the FortiBleed cluster seen earlier this year in June as well as the exposure of adversarial tooling as well as discovery of Tactics, Techniques and Procedures (TTPs) employed by the threat actor known as ‘k0t’. Notable among the observed TTPs is the exploitation of vulnerabilities in network devices such as FortiGate Firewalls and Palo Alto GlobalProtect to gain initial access. Artifacts from this investigation also indicate that operators in this campaign have obtained access to numerous organizations worldwide, and have attempted to further compromise some victims, resulting in persistent remote access and data exfiltration.
From our investigation we also note victim overlaps with several ransomware groups such as Qilin and The Gentlemen, suggesting a possible relationship with ransomware operators or an Initial Access Broker (IAB) role However at this point of the investigation, the relationship between the campaign operators and these ransomware groups, including any direct affiliation, is still unconfirmed.
Due to the large amount of technical information acquired over the course of this investigation, we will be publishing an additional in-depth technical report at a later time.

Key discoveries

• Large-scale campaign involving vulnerability exploitation and brute-forcing of exposed network devices
• More than 70,000 exposed credentials associated with network devices, LDAP dumps etc. which were not linked to any other threat actors, including the previously reported FortiBleed cluster
• Persistent access to corporate networks via OpenConnect VPN as well as installation of Remote Monitoring and Management (RMM) tools as well as AdaptixC2
• Artifacts and ransomware overlaps indicate that this may be an Initial Access operation undertaken by Brokers with association with various ransomware groups.

Who may find this blog interesting:

• Cybersecurity analysts and corporate security teams
• Threat intelligence specialists
• Network security specialists
• Cyber investigators
• Computer Emergency Response Teams (CERT)

Group-IB Threat Intelligence Portal: k0t

Group-IB customers can access our Threat Intelligence portal for more information about this threat actor.

Victimology

Victims we have observed in this campaign are global and from a wide range of industries. This lack of specificity is likely due to the operators’ chosen reconnaissance approach targeting exposed devices such as FortiGate and FortiWeb firewalls, Palo Alto GlobalProtect etc. as such, any analysis done based on the distribution of victims observed in this campaign is likely a reflection of less than ideally configured network devices that are vulnerable to being discovered using public network scanning tools. We also note that many of the FortiGate compromises are dated between February 2026 and June 2026, a stark overlap in timeline with the widely reported FortiBleed campaign.

Since victim identifiers observed vary from public domains and email addresses to internal IPs, exact victim attribution cannot be verified for the entirety of the observed victim list. However, we note some number of  unique domains mentioned in adversarial operational data, and estimate this to be the lower bound of actual victim organizations affected by this campaign.

Of these unique domains, we note the following geographical distribution.

The Asia Pacific and Latin America regions account for the largest share of unique domains identified in the available dataset. However, this distribution should not be interpreted as evidence of deliberate regional targeting. It may instead reflect the geographic distribution of exposed devices identified through public scanning and access-data services.

Attack Chain

Reconnaissance is conducted through public scanning tools rather than target-specific research. Using the attack-surface search engines like FOFA and ZoomEye, the operators enumerate internet-facing VPN and firewall appliances in bulk, filtering candidates by product and exposure to assemble large target lists of potentially vulnerable edge devices. The operators then attempt to gain initial access by attempting to exploit vulnerabilities in the exposed appliances or perform brute force attacks. On successful attack additional credential harvesting is performed at the compromised device, and connection to the targets are achieved via OpenConnect VPN connection. At this stage, majority of the devices seen being targeted are Fortinet firewalls and Palo Alto GlobalProtect devices/portals.

Figure 1. General attack chain observed by campaign operators.

Once initial access has been gained, the operators continue their intrusion via hands-on-keyboard attacks, undertaking discovery activities, performing additional credential theft and attempting to escalate toward domain-administrator control. To ensure they retain access, they establish persistence by deploying remote-management agents such as MeshAgents to control compromised devices from a central MeshCentral server, as well as other more commonly abused Remote Monitoring and Management (RMM) tools such as Atera. Many organizations that have been successfully compromised by the operators in this campaign had data exfiltrated, and have also been listed by various ransomware groups such as Qilin and The Gentlemen.

Reconnaissance

k0t appears to select potential targets by enumerating exposed network appliances at scale rather than researching individual organizations. His stated geographic priorities begin with the United States and Canada, followed by European countries and selected APAC markets. The product and location of an exposed device therefore appear to matter more than the industry of the organization operating it, consistent with the broad range of victims observed in this campaign.

Attack-surface search engines are central to this approach. In a public forum post, k0t sought either a premium FOFA account or someone who could retrieve IP addresses from FOFA, ZoomEye and Censys on request. He later reported finding partners for FOFA and ZoomEye (Figure 2). He also sought bulk results in ip:port format so that target lists could be processed by automated tools.

Figure 2. k0t requests a premium FOFA account or on-demand IP exports from FOFA, ZoomEye and Censys. In a follow-up post, he says he has found partners for FOFA and ZoomEye.

GlobalProtect portals are the most prominent target in the observed searches. k0t searched for login-page, response-content and certificate characteristics, first in North America and then across Europe and APAC. These broad searches could yield large lists of candidate portals, which he requested in a format suitable for automated checking. He also showed interest in FortiWeb and FortiGate systems, while searches for SonicWall SMA1000 management consoles suggest an additional area of interest. OPNsense appears among the products he checked, and his vulnerability monitoring extended to Cisco ISE. Current available evidence does not indicate a successful SMA1000 compromise by k0t.

k0t did not rely on one source of target data. Besides search-engine exports, public forum posts show him using and endorsing underground services that supply bulk, product-filtered IP lists, which included AccessTracker and FortiSSL. Such services give him another way to obtain candidate devices when a direct search-engine export is unavailable. k0t was also observed participating in a public thread offering Fortinet access, showing interest in ready-made access. However there was no clear indication if any credential was received or used. Once gathered, candidate addresses were sorted by country and combined into lists for further checking.

Figure 3. Under the aliases “Member19” and “CryptoFeel,” the intruder left reviews of test runs of a service that provides IP lists of network devices for use in future attacks.

His own checkers provided another layer of validation. An OPNsense checker compared multiple indicators found on a web panel, including certificate and login-page characteristics, to reduce false positives. A separate FortiGate scanner also tested the reachability of management and SSH services on common and alternative ports. Together with geographic sorting, these tools turned large collections of potential targets into smaller sets for assessment. The following Initial Access section describes the Fortinet and GlobalProtect techniques; discovery of a host alone does not mean it was attacked. Public forum activity also indicates an interest in improving attack automation and tracking newly disclosed vulnerabilities.

Initial Access

FortiGate Security Scanner

Initial access into victims’ corporate networks via FortiGate and FortiWeb devices is achieved primarily via a custom script. This script is self-named ‘FortiGate Security Scanner’ (with the filename ‘fort[.]py and ‘fortnew[.]py’) and is used by the operators to exploit CVE-2025-64446 (for FortiWeb services) as well as brute-forcing (as a fall-back method) exposed Fortinet devices. An additional identifier of ‘BH’ was also contained within the script under the field ‘SCRIPT_DEV’. At this point of the investigations however, we have not been able to identify this developer and determine their relationship with k0t.

The tool is built for volume and is executed entirely from the command line, it ingests target ip:port (or ip:port:user:pass) as lines within a .txt file, and runs a configurable worker thread pool (the default is 10 although the operator has been observed to run 50 worker threads), and tags each target’s country from a bundled GeoIP database. It carries a hardcoded exclusion list covering the CIS region and other jurisdictions, but this filter can be disabled with the ‘–no-exclude’ flag. We also note that there are several victims from the excluded nations list being compromised using this tool, indicating that this operator may have used this tool in the ‘–no-exclude’ mode.

CVE-2025-64446 Exploitation

For every device in the target list, the tool first attempts to gain initial access via the exploitation of CVE-2025-64446, a relative path traversal vulnerability affecting Fortinet FortiWeb that may allow an unauthenticated attacker to execute administrative commands through crafted HTTP or HTTPS requests. For each responsive target appliance it issues a crafted request to the ‘/api/v2.0/cmdb/system/admin%3f/../../../../../cgi-bin/fwbcgi’ endpoint. This request contains a forged CGIINFO header that impersonates the built-in admin account ‘prof_admin’, and uses that access to create a new local administrator.

This forged account is given a random eight-character username and an identical password, the prof_admin profile, and a trusted-host range of 0.0.0.0/0 which grants unrestricted administrative access from any source address. When this process is completed, the tool then validates the new credentials over the REST API before proceeding. FortiGate devices are not vulnerable to this exploit, but will be attacked via brute-forcing.

Brute-Forcing

When validation of the newly created account fails, the tool falls back to credential brute-forcing against the FortiGate REST API. When run with a ‘-comb’ flag, the script generates a list of username and login credentials by combining a hardcoded list with an operator supplied wordlist. The resulting wordlist contains common username and passwords such as:

• Usernames
  • admin
  • fortinet
  • fgtsecure
  • sysadmin
  • etc.
• Passwords
  • admin
  • fortigate
  • F0rt!n3t123
  • P@ssw0rd123
  • etc.

When a FortiGate lockout response (“code 2”) is detected, the target will be placed in a dictionary called ‘blocked_hosts’ and no further attempts against that host will be attempted for 60 seconds. After this 60 seconds have elapsed, the blocked host will be removed from ‘blocked_hosts’ and added to a retry queue. We would like to note that 60s is the default administrator lockout time for a FortiGate firewall, which indicates that the developer of this tool possesses significant technical knowledge about the FortiGate appliances.

On a successful authentication attempt after vulnerability exploitation or brute-forcing, and if the ‘–parse-configs’ flag is set, the tool downloads the appliance configuration and decrypts its stored secrets locally, using the default FortiOS AES key, to recover LDAP/Active Directory bound credentials, administrator and local-user credentials, and other configuration data. The ‘default FortiOS AES key’ is a known weakness tracked under CVE-2019-6693. Its associated fix is the addition of ‘private-data-encryption’ option to override the usage of this default AES key; if not toggled explicitly, the affected device will fall back to using this known key.

PAN-OS GlobalProtect Exploitation

Threat Intelligence analysts have also observed the exploitation of CVE-2026-0257, an authentication bypass vulnerability affecting GlobalProtect portals and gateways on vulnerable PAN-OS configurations where authentication-override cookies and the relevant certificate configuration are enabled, to gain initial access. The operator makes use of a tool (filename ‘exploit_2026_0257[.]py’) with the self-declared descriptor/name ‘CVE-2026-0257 PAN-OS GlobalProtect Scanner + VPN Connect’,  written by a developer named ‘BeiDou’.

The exploit entails the use of authentication-override cookie forgery, where a forged cookie is created by encrypting the string ‘admin;;Windows;;[TIMESTAMP];0.0.0.0’ (where [TIMESTAMP] is the current UNIX timestamp) with a public key extracted from the target’s TLS certificate. This forged cookie with an empty password is submitted to the GlobalProtect endpoint ‘/ssl-vpn/login.esp’.

A vulnerable device would decrypt this payload using its private key and check for the appropriate session format, but does not validate that the cookie itself is legitimate. Such a device would respond to this forged request and be flagged by the tool for further exploitation. For every vulnerable device, the forged cookie is written into a temporary file, and used to establish a vpn connection via OpenConnect. This is achieved by creating and running a temporary shell script on the operator’s own device.

When run in a –vuln mode, the operator can skip through the mass-scanning process and will be presented with a window for target selection to establish VPN connection.

Figure 4. Console interface of CVE-2026-0257 PAN-OS GlobalProtect Scanner + VPN Connect tool in the –vuln mode. The tool lists vulnerable targets available from a .txt file for the operator’s selection to attempt compromise.

This is ostensibly meant to be used on targets where cookies (either forged or stolen via other means) are already obtained.

Post Exploitation

Once initial access has been obtained, the operators have been observed abusing several administrator/pentesting tools to further compromise their victim’s corporate environments. These tools have been observed to be deployed via hands-on-keyboard attacks although an AI pentesting tool was observed to be present among the operator’s exposed tooling, we do not have evidence of its actual deployment against their victims and was likely still in development. Administrator/Pentesting tools observed include:

• NetExec – The operators have been observed using NetExec extensively to perform malicious actions in their victim’s environments. These include, but are not limited to:
  • Enumeration of SMB hosts, anti-virus inventory, LDAP domain admin groups, files and folders
  • Extracting secrets from SAM, LSA, LSASS, DPAPI
  • Remote execution of commands via ‘atexec’ or ‘smbexec’
• SoftPerfect – We have observed the usage of SoftPerfect for discovery, enumerating shares, hosts and services
• Impacket – Various Impacket scripts by the operators in order to:
  • GetUserSPNs – to extract service-account Kerberos hashes
  • secretsdump – authenticate as a domain controller using stolen hashes to extract credentials
• noPac – This tool was used to exploit CVE-2021-42278 and CVE-2021-42287 to escalate to Domain Admin and dump domain credentials
• Kerbrute – Used for password-spraying and brute-forcing attacks against the domain controller
• PetitPotam – Seen used to coerce domain controllers into authenticating to the operator’s relay listener (-pipe all), feeding the NTLM-relay-to-ADCS certificate-theft chain that yields the DC machine hash.
• Mimikatz – Seen used to dump cleartext passwords and NTLM hashes from LSASS.

Artifacts also suggest that subsets of the initial access obtained have been consolidated for other operators (for division of labour), and potentially to be sold to ransomware groups.

Persistence

Within the operator’s exposed tooling, we have observed a large variety of persistence techniques and utilities being abused. As was mentioned in previous sections, the operators made use of OpenConnect to establish a foothold on many exposed corporate networks. However, beyond OpenConnect, we have also observed the abuse of MeshAgents (controlled via a MeshCentral panel) as well as AdaptixC2, and many other commonly abused RMM tools such as Atera, Teramind, AnyDesk and ngrok.

MeshCentral

MeshCentral is a legitimate, open-source web-based remote-management platform that has been abused in this campaign to maintain persistent remote access to a compromised endpoint. A central server, called MeshCentral, hosts an administrative web console, with corresponding MeshAgents which are installed on endpoints connecting to that server over HTTPS/WebSocket, giving whoever has access to the MeshCentral server full remote control of each device. Access via MeshCentral includes remote desktop, terminal shell, file transfer etc.

Figure 5. k0t’s MeshCentral login page at mesh[.]buttruyen[.]com.

Compromised devices are grouped into “device groups” corresponding to the compromised corporations, and are divided among three operator accounts. At the time of analysis, we were able to determine 28 active device groups, which contained 84 compromised devices in total beaconing back to the MeshCentral server at mesh[.]buttruyen[.]com. Artifacts also showed 100 other device groups which have since been removed. Notably, the server held no server-side files, indicating the agents were used for live interactive access only (shell and RDP relay) rather than for data transfer, which was handled separately by Rclone.

While the MeshCentral server was located at mesh[.]buttruyen[.]com, the MeshAgents are hosted on another domain, agent[.]afahimsa[.]top. This is likely an attempt by the operators to lower the likelihood of researchers discovering their C2 MeshCentral server. The MeshCentral server is configured with agentAutoApprove, agentAutoCreateDevice, IgnoreAgentHashCheck and agentInviteCodes options enabled so that each successful installation would automatically result in the compromised device being automatically enrolled into the console without any operator intervention.

AdaptixC2

AdaptixC2 is an open-source, modular post-exploitation and adversary-emulation framework consisting of a Go-based team server and a Qt operator client. In this campaign, the operators used it as an additional command-and-control (C2) channel alongside MeshCentral. Windows agents generated through the team server communicate over HTTPS and provide remote shell access, file transfer, tunnelling, and payload execution.

Build notes and a deployment guide recovered from the operators’ tooling exposed details of their AdaptixC2 configuration. The guide instructed the operators to compile AdaptixC2 from its public repository, generate a default self-signed OpenSSL certificate, and edit profile.json to set the listening interface, team-server port, endpoint, and operator accounts. The observed profile retained the default port 4321, used /endpoint as the team-server endpoint, and contained two operator accounts, operator1 and operator2. The operators also created listeners using the following URIs:

• /update
• /api/v1/check
• /uri.php

Operators also loaded the AdaptixC2 Extension-Kit, which is a collection of scripts designed to add essential utilities, and had also compiled AdaptixC2 agents as Windows executables.

The resulting team server was reachable at hxxps://64[.]94[.]85[.]14:4321/endpoint, however, access was restricted to the operators’ source addresses, which likely explains why the service did not appear in internet-wide scan data. The TLS certificate retained the default subject O=Internet Widgits Pty Ltd. Third-party sources also classified the IP address as malicious, supporting our assessment that it hosted active C2 infrastructure.

AdaptixC2 agents were staged on separate infrastructure and delivered as a fake software installer named clear-thinking_61.92.4_INSTALL.exe. We have observed operators using PowerShell scripts to retrieve these agents from hxxp://162[.]33[.]178[.]213:8888/ and hxxps://sthyjk[.]com:8443/ using curl commands. Both locations pointed to the same host, to which an additional domain, alknene[.]shop, also resolved.

The beacons were configured to communicate with:

• 64[.]94[.]85[.]14:4321
• 168[.]100[.]11[.]99

Which were hosted by BitLaunch (AS399629), an anonymous VPS provider that accepts cryptocurrency, as were other infrastructure seen in this campaign. The associated domains were registered through Namecheap.

Operator organization

Available evidence associated with the identified MeshCentral and AdaptixC2 infrastructure indicates the likely involvement of multiple operators, suggesting a collaborative operation rather than activity conducted by a single threat actor.  From our investigations into this cluster, we have preliminarily identified the following aliases to be associated with this activity:

• k0t – Likely to be one of the main operators in this campaign
• CryptoFeel – Potentially an alias of k0t
• Scrooge/ScroogeMcDuck – Likely a collaborator, and potentially another alias, several tools seen are likely to have been acquired by Scrooge

Developers mentioned in this report have not been linked directly to the campaign’s operations, and are potentially free-lance developers used by multiple threat actors. As investigations continue, we expect to learn more about how this campaign is managed and organized. Additional information will be provided in updates as they become available.

Conclusion

In the few victims that the operators have managed to compromise sufficiently, we have observed data exfiltration via the cloud storage utility Rclone into Wasabi S3 buckets and MEGA cloud drives. Many victims seen in this campaign have also been observed to be later listed by ransomware groups, Qilin and the Gentlemen, on their Data Leak Sites (DLS). However, as of now, we have not yet been able to confirm the relationships between k0t and these ransomware groups, but current evidence suggests that the operators are likely to be acting as Initial Access Brokers (IABs).

We have compared the compromised credentials from this activity with that associated with the previously reported FortiBleed cluster and found a negligible overlap in compromised data. This aligns with reports that many operators are likely to be involved in the FortiBleed activity cluster, suggesting that this may be a separate dataset, operator subset, or related access operation within the broader FortiBleed-related activity. Organisations are advised to act on ensuring that any vulnerabilities mentioned in this report are appropriately remedied. Additional information from our ongoing investigations into this activity, including additional technical details, will be included in a further report which will be released in due time.

Context for Organizations within the Asia-Pacific region

Accounts originating from the Asia-Pacific region account for 37.6% of the unique domains identified in the campaign dataset, the largest regional share in this investigation. This distribution should not be interpreted as proof of deliberate regional targeting because it may reflect the geographic distribution of exposed or inadequately configured edge devices discovered through public scanning services.

For organisations within the Asia-Pacific, the practical priority is exposure-led rather than sector-led: identify internet-facing FortiGate, FortiWeb and GlobalProtect systems; verify patch and configuration status; restrict management access; review administrative and VPN authentication; and assess whether credentials stored on or accessible through these appliances require rotation.

Comparison with the Previously Reported FortiBleed Activity

The comparison below distinguishes confirmed observations from analytical assessment. Public descriptions of FortiBleed differ in scope, so the table uses Fortinet’s June 2026 assessment for the previously reported activity and this investigation’s evidence for the k0t cluster.

The association remains an analytical assessment and does not establish that the same operators controlled both datasets.

NyxLab Defender Perspective

The following points translate the campaign evidence into defensive priorities. They are derived from the artifacts described in this report and should not be read as confirmation that every behaviour occurred in every victim environment.

Why detection can be difficult

The intrusion begins on edge appliances where endpoint detection and response telemetry may not be available. Subsequent access through VPN services and legitimate remote-management tools may resemble authorised administrative activity unless network, identity, appliance and endpoint telemetry are correlated.

The use of dual-use tools, including OpenConnect, MeshCentral, Atera, AnyDesk and Rclone, means detections should consider execution context, installation source, operator account, destination infrastructure and timing rather than relying only on tool names.

Threat-hunting priorities

• Edge appliances: review unexpected local administrator creation, configuration exports, trusted-host changes, repeated authentication failures, lockout-and-retry patterns, and administration from unusual source addresses.
• VPN and identity: review GlobalProtect and other VPN sessions for unusual client characteristics, atypical access paths, newly observed source infrastructure, and accounts used outside normal administrative patterns.
• Windows and Active Directory: hunt for NetExec, Impacket, noPac, Kerbrute, PetitPotam and Mimikatz activity, including credential dumping, service-account Kerberos requests, remote execution, and abnormal domain-controller authentication.
• Persistence and command and control: identify unauthorised MeshAgent, MeshCentral, AdaptixC2, Atera, Teramind, AnyDesk and ngrok installations or communications, and validate whether each instance has an approved owner and business purpose.
• Exfiltration: investigate unexpected Rclone execution and transfers to cloud-storage services, including Wasabi S3 and MEGA, particularly when preceded by credential access or broad file enumeration.

Business and incident-response implications

A compromise of an internet-facing security appliance should be treated as a potential enterprise credential compromise, not only as an appliance-patching event. Because configuration data may contain LDAP, Active Directory, administrator and local-user secrets, responders should assess downstream identity exposure, rotate affected credentials, revoke active sessions where applicable, and review subsequent access across the environment.

Immediate actions for exposed organisations

• Confirm the external exposure and patch status of FortiGate, FortiWeb and Palo Alto GlobalProtect systems, and remove management interfaces from direct internet access where operationally possible.
• Review appliance administrator accounts and recent configuration changes, and investigate any account or trusted-host setting that cannot be linked to an authorised change.
• Rotate credentials stored on, bound to or administered through potentially affected appliances, prioritising privileged, LDAP and Active Directory accounts.
• Search for the network indicators and file hashes in this report, while recognising that the absence of an IOC match does not rule out compromise.
• Preserve appliance, VPN, authentication, endpoint, DNS, proxy and firewall telemetry before retention periods expire, and correlate events across these sources to reconstruct

Recommendations

Readers who wish to check if they are compromised by this activity can contact Group-IB and/or NyxLab for additional information.  Organizations that have identified signs of compromise, such as unauthorized access to FortiGate or other edge appliances, exposed configuration files, or suspicious use of LDAP/AD bind accounts, can engage Group-IB Incident Response for investigation, containment and remediation. Please contact us via the following channels:

• Group-IB contact form
• NyxLab: [email protected]

Network Hardening – threat actors in this campaign relied heavily on discovery of network devices via public tools which are followed by attempts at brute-forcing

• Place network management consoles within an internal network and restrict access to trusted administrative networks or VPN connections. This reduces their exposure to internet-wide scanning and requires threat actors to first gain access to the internal network.
• Refrain from using common passwords. Organizations are advised to change default passwords as soon as they can and refrain from using passwords which are commonly used in brute-forcing attacks
• Increasing login lockout time can also deter threat actors from successfully carrying out a brute-forcing attack. Multiple failed attempts resulting in login lockout status should also be investigated by analysts
• Maintain continuous visibility into internet-facing assets. Group-IB Attack Surface Management can identify unintentionally exposed administrative panels, VPN portals, and other management interfaces, allowing organizations to remediate unintended exposure before threat actors discover it.

Patch Management – The operators in this campaign targeted vulnerabilities in network devices for initial access. k0t in particular has also been active on underground forums looking to acquire tools for similar exploits targeting common network devices (such fortigate, cisco, sonicwall etc.) as well as Windows privilege escalation

• Ensure that devices in your organization are patched in a timely manner, prioritising internet facing network devices. Proper prioritization of vulnerabilities according to their impact and severity will also help custodians manage limited resources towards remediating more severe vulnerabilities
• Frequent vulnerability scanning and asset discovery should also be conducted to discover unknown vulnerabilities that persist in the organization

Protect Stored Appliance Secrets – In this campaign, the operators downloaded FortiGate configuration files after gaining access and decrypted them offline to recover the credentials stored inside, including LDAP and Active Directory bind accounts, administrator accounts, local users and other configuration data. Because this decryption is performed against a copy of the configuration held by the operator, it is not detectable on the appliance itself and cannot be prevented by access control alone; the protection must be applied to the stored secrets.

• Enable the ‘private-data-encryption’ setting on FortiGate appliances and supply an operator-defined key. FortiGate configuration files are encrypted with a default, publicly known AES key unless this setting is explicitly enabled. If it is not toggled on, the appliance falls back to the known key and any obtained configuration can be decrypted by anyone who holds it. This is tracked as CVE-2019-6693 and is the specific weakness the operators in this campaign exploited at scale.
• Treat any FortiGate whose configuration has been exposed as a credential disclosure event, not only as an appliance compromise. Configuration data commonly contains LDAP and Active Directory bind passwords in a recoverable form. Rotate every credential referenced in an affected configuration, including service and bind accounts that may not appear in routine password rotation schedules.

• Audit LDAP and directory bind accounts used by edge appliances. These accounts are frequently service accounts with broad read access to the directory, are rarely covered by MFA, and are often excluded from routine password rotation. Where the appliance supports it, use a dedicated low-privilege bind account rather than a domain administrator or equivalent.

Enforce Strict MFA – Apply Multi-Factor Authentication universally to all accounts where applicable to minimize the threat of stolen plaintext passwords.

Enhance Threat Detection and Response – Organizations should maintain visibility across endpoint, network, identity, and other relevant telemetry to identify malicious activity following the compromise of internet-facing appliances. Group-IB Managed XDR together with  Group-IB Threat Intelligence can help organizations correlate suspicious activity with known threat actor infrastructure, TTPs, and indicators associated with this campaign.

• Monitor for abnormal authentication activity, credential access, privilege escalation, and lateral movement following access through VPN or edge appliances.
• Detect unauthorized or unusual use of remote administration and command-and-control tools, including RMM software and other dual-use utilities.
• Correlate endpoint, network, and identity telemetry to identify activity that may appear legitimate when individual events are reviewed in isolation.
• Use threat intelligence to enrich detections with relevant indicators, infrastructure, and TTPs associated with k0t and related activity.

Rotate potentially compromised credentials – if there is any reasonable suspicion that an account has been compromised (via listing on compromised accounts or observation of suspicious behavior etc.) rotate credentials for the affected accounts, or delete the accounts if not in use.

Compromise Monitoring – Group-IB have obtained information regarding compromised victim accounts. Such compromised information will be available on the ‘Compromises’ module on TAP.

• Keep your organization’s assets up to date. Such feeds rely on positive identification of your organization’s assets within the discovered collection of compromised accounts, keeping such asset lists up to date whenever possible will decrease the likelihood of a failed notification to a positive hit

MITRE ATT&CK

Indicators of Compromise (IOCs)

Network IOCs

MeshCentral C2

• mesh[.]buttruyen[.]com
• 62[.]60[.]131[.]43
• Meshcentral[.]girydsfsggvb[.]com
• 62[.]60[.]135[.]64

MeshAgent payload hosting

• hxxps://agent[.]afahimsa[.]top/meshagents?id=4&meshid=DSZSDHzU1YSP83eNnHzSUfPPt5MFUC3UadztK7UJWbWttVfTo$auq8StiVu0p6ND&installflags=0
• hxxp://193[.]149[.]187[.]81:1287/1.exe

AdaptixC2 server

• 64.94.85.14
• 168.100.11.99

AdaptixC2 download

• hxxp://162[.]33[.]178[.]213:8888/clear-thinking_61.92.4_INSTALL.exe
• hxxps://sthyjk[.]com:8443/clear-thinking_61.92.4_INSTALL.exe

Development & tool staging  Server

• 162[.]33[.]179[.]249
• 193[.]24[.]123[.]162
• 193[.]149[.]176[.]50

Nezha dashboard C2

• radesashar[.]com

Potential scanning infrastructure

• 193[.]169[.]194[.]21

File Hashes

• 5318f29ef434341d989d543b14fd2a48
• 6546801898d0b32f5050f49c5302f0366d630cc9
• 158215c7371e868f3d0c7fd2e92f05026a8678a3635629d89bd6042ee543278a
• 20dc8f1b8a313336c14e03bcb71ff6c8
• e2c96e603323d8fc7c08678b793d56554faa6914
• 1d1b76d30a69aa39b224053481483156f82dde026edd6f5d964f6e03f5f04a6d
• 032473db4d66748eab524effe57a661d
• b686a811ad89671fbdb448d65f79488d2e562265
• 4db6bea4c1e4bce5020039def4087a073f4753a6b297b2832c19c10423ac842d
• 13367fbba4344de87de418ab17de76f0
• f05daaf66b200672d679a5ced8b67d4b48a4906e
• 552d0096f60c36a35c6096b3e4b38d743c29f8c56f3862fa3b7ef06c932e2a21
• 197f2621c80da7974c56d2ff1921e994
• e47a2b7ca6a8c009962871dbb667d128ad6b6162
• f9e95af4cda14dd5596c452a1a698f60412a7b2a9540321ee2a10b3bcbbd2a0e
• 6f5d18157425aa9697913ae1310f588f
• bfd864ec0e6bd912f932e4f3ed80687736ee16e8
• 39c4decc4881ec02a47cd01c0fd8c3030527b466124ad03c6f99cfaa0ba0b72e
• 0dc1af7cfd336a7f075228defc730082
• b39cf70a0194d32e00d7812c29ae1d6add77b823
• 808145ec3351569083fda27a910ebdf9e054e8ca42e40c021af5d6712c2ab87c

DISCLAIMER: All technical information, including malware analysis, indicators of compromise and infrastructure details provided in this publication, is shared solely for defensive cybersecurity and research purposes. Group-IB and NyxLab do not endorse or permit any unauthorized or offensive use of the information contained herein. The data and conclusions represent Group-IB’s analytical assessmentThe data and conclusions represent the joint analytical assessment of Group-IB and NyxLab based on available evidence and are intended to help organizations detect, prevent, and respond to cyber threats.

Group-IB and NyxLab expressly disclaim liability for any misuse of the information provided. Organizations and readers are encouraged to apply this intelligence responsibly and in compliance with all applicable laws and regulations.

This blog may reference legitimate third-party services such as Telegram and others, solely to illustrate cases where threat actors have abused or misused these platforms.

This material is provided for informational purposes, prepared jointly by Group-IB and NyxLab as part of their collaborative investigation, and reflects recently identified threat activity.

All trademarks referenced herein are the property of their respective owners and are used solely for informational purposes, without any implication of affiliation or sponsorship.