Detections
- Home
- - Detections
- -DT098
- ID: DT098
- Created: 31st July 2024
- Updated: 31st July 2024
- Contributor: Ismael Briones-Vilar
NetFlow Analysis
Analyze network flow data (NetFlow) to identify unusual communication patterns and potential tunneling activities. Flow data offers insights into the volume, direction, and nature of traffic.
NetFlow, a protocol developed by Cisco, captures and records metadata about network flows—such as source and destination IP addresses, ports, and the amount of data transferred.
Various network appliances support NetFlow, including Next-Generation Firewalls (NGFWs), network routers and switches, and dedicated NetFlow collectors.
Sections
ID | Name | Description |
---|---|---|
AF023 | Browser or System Proxy Configuration | A subject configures either their web browser or operating system to route HTTP and HTTPS traffic through a manually defined outbound proxy server. This action enables them to redirect web activity through an external node, effectively masking the true destination of network traffic and undermining key layers of enterprise monitoring and control.
By placing a proxy between their endpoint and the internet, the subject can obscure final destinations, bypass domain-based filtering, evade SSL inspection, and suppress logging artifacts that would otherwise be available to investigative teams. This behavior, when unsanctioned, is a hallmark of anti-forensic preparation—often signaling an intent to conceal exfiltration, contact unmonitored services, or test visibility boundaries. While proxies are sometimes used for legitimate troubleshooting, research, or sandboxing purposes, their use outside approved configurations or infrastructure should be treated as an investigatory lead.
Technical MethodBoth browsers and operating systems offer mechanisms to define proxy behavior. These configurations typically involve:
Once defined, the behavior is as follows:
Proxy settings may be configured through user interfaces, system preferences, environment variables, or policy files—none of which necessarily require administrative privileges unless endpoint controls are in place.
This technique is especially potent in organizations with reliance on DNS logs, web filtering, or SSL interception as primary visibility mechanisms. It fractures investigative fidelity and should be escalated when observed in unauthorized contexts. |
PR007 | CCTV Enumeration | The subject enumerates organizational CCTV coverage through physical reconnaissance, network-based probing, or a combination of both. This behavior aims to identify surveillance blind spots, coverage patterns, and system weaknesses in order to plan insider activity such as unauthorized entry, covert data removal, or sabotage.
When combined, physical and network enumeration provide a sophisticated map of surveillance infrastructure. For example, a subject may confirm camera placement through on-site observation, then validate viewing angles and live coverage zones by remotely accessing the corresponding camera feeds across the network. This dual approach allows the subject to identify exact surveillance gaps, test whether specific areas are monitored, and plan movement or concealment with high confidence.
This behavior is a strong indicator of deliberate preparation, as it requires technical effort, situational awareness, and intent to circumvent organizational surveillance. |
IF027 | Installing Malicious Software | The subject deliberately or inadvertently introduces malicious software (commonly referred to as malware) into the organization’s environment. This may occur via manual execution, automated dropper delivery, browser‑based compromise, USB usage, or sideloading through legitimate processes. Malicious software includes trojans, keyloggers, ransomware, credential stealers, remote access tools (RATs), persistence frameworks, or other payloads designed to cause harm, exfiltrate data, degrade systems, or maintain unauthorized control.
Installation of malicious software represents a high-severity infringement, regardless of whether the subject's intent was deliberate or negligent. In some cases, malware introduction is the culmination of prior behavioral drift (e.g. installing unapproved tools or disabling security controls), while in others it may signal malicious preparation or active compromise.
This Section is distinct from general “Installing Unapproved Software”, which covers non‑malicious or policy-violating tools. Here, the software itself is malicious in purpose or impact, even if delivered under benign pretenses. |
IF004.005 | Exfiltration via Protocol Tunneling | A subject exfiltrates data from an organization by encapsulating or hiding it within an otherwise legitimate protocol. This technique allows the subject to covertly transfer data, evading detection by standard security monitoring tools. Commonly used protocols, such as DNS and ICMP, are often leveraged to secretly transmit data to an external destination. Prerequisites:
Steps: 1. The subject uses xxd to create a hex dump of the file they wish to exfiltrate. For example, if the file is secret.txt:
2. The subject splits the hexdump into manageable chunks that can fit into DNS query labels (each label can be up to 63 characters, but it’s often safe to use a smaller size, such as 32 characters):
3. The subject uses dig to send the data in DNS TXT queries. Looping through the split files and sending each chunk as the subdomain of example.com in a TXT record query:
On the target DNS server that they control, the subject captures the incoming DNS TXT record queries on the receiving DNS server and decode the reassembled hex data from the subdomain of the query.
DNS Tunneling (Windows)
Prerequisites:
Steps:
2. The subject splits the hex data into manageable chunks that can fit into DNS query labels (each label can be up to 63 characters, but it’s often safe to use a smaller size, such as 32 characters):
3. The subject sends the data in DNS TXT queries. Looping through the hex data chunks and sending each chunk as the subdomain of example.com in a TXT record query:
The subject will capture the incoming DNS TXT record queries on the receiving DNS server and decode the reassembled hex data from the subdomain of the query.
ICMP Tunneling (Linux) Prerequisites:
Steps: 1. The subject uses xxd to create a hex dump of the file they wish to exfiltrate. For example, if the file is secret.txt:
2. The subject splits the hexdump into manageable chunks. ICMP packets have a payload size limit, so it’s common to use small chunks. The following command will split the hex data into 32-byte chunks:
3. The subject uses ping to send the data in ICMP echo request packets. Loop through the split files and send each chunk as part of the ICMP payload:
The subject will capture the incoming ICMP packets on the destination server, extract the data from the packets and decode the reassembled the hex data. |
AF018.001 | Endpoint Tripwires | A subject installs custom software or malware on an endpoint, potentially disguising it as a legitimate process. This software includes tripwire logic to monitor the system for signs of security activity.
The tripwire software monitors various aspects of the endpoint to detect potential investigations:
Upon detecting security activity, the tripwire can initiate various evasive responses:
|
AF018.002 | Environment Tripwires | The subject develops a custom API that monitors specific activities, network traffic, and system changes within the target environment. The API could monitor HTTP/HTTPS requests directed at sensitive endpoints, track modifications to security group settings (such as firewalls or access policies), and identify administrative actions like changes to user accounts, data access requests, or logging configurations.
This tripwire API is embedded within various parts of the environment:
Once deployed, the tripwire API continuously monitors network traffic, API calls, and system changes for indicators of an investigation. It looks for:
The API can use whitelists for expected IP addresses or user accounts, triggering alerts if unexpected access occurs.
Upon detecting activity, the API tripwire can take immediate evasive actions:
|
IF009.006 | Installing Crypto Mining Software | The subject installs and operates unauthorized cryptocurrency mining software on organizational systems, leveraging compute, network, and energy resources for personal financial gain. This activity subverts authorized system use policies, degrades operational performance, increases attack surface, and introduces external control risks.
Characteristics
Example ScenarioA subject installs a customized |
MT017.001 | Nation-State Alignment | The subject is a current or former asset of a nation-state intelligence service, operating inside the organization with pre-existing loyalty to, or direct affiliation with, a foreign government. Unlike insiders who develop espionage motives post-employment, this subject is often inserted, recruited prior to hiring, or cultivated externally over time and then encouraged to seek access to a target organization.
Their motive is the advancement of strategic objectives on behalf of a foreign nation-state. These objectives may include extracting sensitive information, degrading operational resilience, manipulating internal systems or decisions, weakening public or partner trust, or embedding long-term access for future exploitation. Such subjects may be formal intelligence officers, contract operatives, ideological affiliates, or individuals acting under recruitment, coercion, or influence.
Example Scenarios:
|
PR003.012 | Installation of Dark Web-Capable Browsers | The subject installs a browser capable of accessing anonymity networks, such as the Tor Browser (used for
Installation of the Tor Browser Bundle typically involves downloading a signed executable or compressed package from
In environments with proxy filtering, the subject may attempt to chain Tor through bridge relays or VPNs, obfuscate traffic using SOCKS5 tunneling, or execute from non-standard directories (e.g., cloud-sync folders, external volumes). Some subjects bypass endpoint controls entirely by booting into live-operating systems (e.g., Tails, Whonix) which route all system traffic through Tor by default and leave minimal forensic artifacts on host storage.
This installation is rarely accidental and often coincides with other policy evasions or drift indicators. The presence of anonymizing tools—even in dormant form—warrants scrutiny as a preparatory indicator linked to potential data exfiltration, credential harvesting, or external coordination. |
IF027.001 | Infostealer Deployment | The subject deploys credential-harvesting malware (commonly referred to as an infostealer) to extract sensitive authentication material or session artifacts from systems under their control. These payloads are typically configured to capture data from browser credential stores (e.g.,
Infostealers may be executed directly via compiled binaries, staged through malicious document macros, or loaded reflectively into memory using PowerShell, .NET assemblies, or process hollowing techniques. Some variants are fileless and reside entirely in memory, while others create persistence via registry keys (e.g.,
While often associated with external threat actors, insider deployment of infostealers allows subjects to bypass authentication safeguards, impersonate peers, or exfiltrate internal tokens for later use or sale. In cases where data is not immediately exfiltrated, local staging (e.g., in |
IF027.002 | Ransomware Deployment | The subject deploys ransomware within the organization’s environment, resulting in the encryption, locking, or destructive alteration of organizational data, systems, or backups. Ransomware used by insiders may be obtained from public repositories, affiliate programs (e.g. RaaS platforms), or compiled independently using commodity builder kits. Unlike external actors who rely on phishing or remote exploitation, insiders often bypass perimeter controls by detonating ransomware from within trusted systems using local access.
Ransomware payloads are typically compiled as executables, occasionally obfuscated using packers or crypters to evade detection. Execution may be initiated via command-line, scheduled task, script wrapper, or automated loader. Encryption routines often target common file extensions recursively across accessible volumes, mapped drives, and cloud sync folders. In advanced deployments, the subject may disable volume shadow copies (vssadmin delete shadows) or stop backup agents (net stop) prior to detonation to increase impact.
In some insider scenarios, ransomware is executed selectively: targeting specific departments, shares, or systems, rather than broad detonation. This behavior may indicate intent to send a message, sabotage selectively, or avoid attribution. Payment demands may be issued internally, externally, or omitted entirely if disruption is the primary motive. |
IF027.003 | Keylogger Deployment | The subject deploys software designed to record keystrokes entered on an endpoint to capture credentials, sensitive communications, internal documentation, or intellectual property. Keyloggers may be introduced as standalone binaries, embedded within otherwise legitimate tools, or configured through dual-use frameworks (e.g. C++ dropper with keylogging module). In insider scenarios, the deployment is typically local and deliberate, leveraging the subject’s physical access or assigned privileges to bypass existing controls.
Keyloggers operate in one of several modes:
Captured data is typically stored in encrypted local files (e.g. |
IF027.004 | Remote Access Tool (RAT) Deployment | The subject deploys a Remote Access Tool (RAT): a software implant that provides covert, persistent remote control of an endpoint or server—enabling continued unauthorized access, monitoring, or post-employment re-entry. Unlike sanctioned remote administration platforms, RATs are deployed without organizational oversight and are often configured to obfuscate their presence, evade detection, or blend into legitimate activity.
RATs deployed by insiders may be off-the-shelf tools (e.g. njRAT, Quasar, Remcos), lightly modified open-source frameworks (e.g. Havoc, Pupy), or commercial-grade products repurposed for unsanctioned use (e.g. AnyDesk, TeamViewer in stealth mode).
Functionality typically includes:
Deployment methods include manual installation, script-wrapped droppers, DLL side-loading, or execution via LOLBins ( |
IF027.005 | Destructive Malware Deployment | The subject deploys destructive malware; software designed to irreversibly damage systems, erase data, or disrupt operational availability. Unlike ransomware, which encrypts files to extort payment, destructive malware is deployed with the explicit intent to delete, corrupt, or disable systems and assets without recovery. Its objective is disruption or sabotage, not necessarily for direct financial gain.
This behavior may include:
Insiders may deploy destructive malware as an act of retaliation (e.g. prior to departure), sabotage (e.g. to disrupt an investigation or competitor), or under coercion. Detonation may be manual or scheduled, and in some cases the malware is disguised as routine tooling to delay detection.
Destructive deployment is high-severity and often coincides with forensic tampering or precursor access based infringements (e.g. file enumeration or backup deletion). |