Attor
Attor is a Windows-based cyberespionage platform first publicly documented by ESET in 2019, with observed activity dating back to at least 2013. It is a modular malware platform whose dispatcher can execute additional plugins by loading DLLs. Reported capabilities include automatic collection of compromised-system information, clipboard theft via the OpenClipboard and GetClipboardData APIs, collection of information about inserted storage devices, modems, and phone devices, and audio recording through available input sound devices. Attor stages collected data in a central upload directory prior to exfiltration and exfiltrates data over its command-and-control channel. It has used Tor for C2 communication, and its Blowfish key is encrypted with a public RSA key. For persistence, Attor’s dispatcher can register a new Windows service, and its installer plugin can schedule a task that loads the dispatcher on boot or logon; reporting also notes the installer plugin could schedule rundll32.exe to load the dispatcher. For defense evasion and privilege-related tradecraft, the dispatcher can inject itself into running processes to gain higher privileges and evade detection, log files and directories can be marked with HIDDEN, SYSTEM, and ARCHIVE attributes, and the malware manipulates last-access timestamps of files and registry keys after creation or modification. Additional observed behavior includes opening the Windows Registry and performing query searches. Separate reporting cited in the content states that an Attor plugin used the BITS IBackgroundCopyJob interface to communicate with a C2 server and used COM-exposed functionality to launch VBScript and PowerShell, while IWbemClassObject was used to enumerate installed endpoint security software.
Hunt this family in your stack
Mallory pivots from this family to the IOCs, detections, and named campaigns that touch your stack, and pages you when something new lands.
Techniques & procedures
27 distinct techniques documented for this family, organized by ATT&CK tactic.
Execution
4 techniques
Execution
During the 2022 Ukraine Electric Power Attack, Sandworm Team leveraged Scheduled Tasks through a Group Policy Object (GPO) to execute CaddyWiper at a predetermined time.
The same COM object may be created from VBScript, PowerShell, Python, or C/C++... The same plugin also contains COM exposed functionality for launching VBScript and PowerShell through COM client code.
Astaroth uses the LoadLibraryExW() function to load additional modules. Attor's dispatcher can execute additional plugins by loading the respective DLLs. ... LightSpy's main executable and module .dylib binaries are loaded using ... dlopen() ... dlsym() ... RotaJakiro uses ... .so files ... using dlopen() and dlsym().
Background Intelligent Transfer Service (BITS) is another COM-exposed Windows service that attackers use... The IBackgroundCopyJob interface is used to add files to a job, set priority, determine state, and start or stop transfers. Malware using this interface may perform payload download, staging, or exfiltration... In the example used here, the Attor plugin uses IBackgroundCopyJob to communicate with a C2 server.
Persistence
5 techniques
Persistence
During the 2022 Ukraine Electric Power Attack, Sandworm Team leveraged Scheduled Tasks through a Group Policy Object (GPO) to execute CaddyWiper at a predetermined time.
The content repeatedly describes threat actors and malware modifying, creating, deleting, or storing data in Windows Registry keys and values for persistence, configuration storage, defense evasion, credential access, privilege escalation, and execution.
Background Intelligent Transfer Service (BITS) is another COM-exposed Windows service that attackers use... The IBackgroundCopyJob interface is used to add files to a job, set priority, determine state, and start or stop transfers. Malware using this interface may perform payload download, staging, or exfiltration... In the example used here, the Attor plugin uses IBackgroundCopyJob to communicate with a C2 server.
During the 2016 Ukraine Electric Power Attack, Sandworm Team used an arbitrary system service to load at system boot for persistence for Industroyer. They also replaced the ImagePath registry value of a Windows service with a new backdoor binary.
Agent Tesla can achieve persistence by modifying Registry key entries. Attor's dispatcher can modify the Run registry key. Kimsuky has also modified the registry entry for HKCU:\Software\Microsoft\Windows\CurrentVersion\Run registry key for persistence with the name WindowsSecurityCheck. PLAINTEE uses reg add to add a Registry Run key for persistence.
Privilege Escalation
4 techniques
Privilege Escalation
During the 2022 Ukraine Electric Power Attack, Sandworm Team leveraged Scheduled Tasks through a Group Policy Object (GPO) to execute CaddyWiper at a predetermined time.
The content repeatedly describes adversaries and malware injecting code, shellcode, DLLs, or payloads into legitimate processes such as svchost.exe, explorer.exe, iexplore.exe, wuauclt.exe, lsass.exe, and browser processes.
During the 2016 Ukraine Electric Power Attack, Sandworm Team used an arbitrary system service to load at system boot for persistence for Industroyer. They also replaced the ImagePath registry value of a Windows service with a new backdoor binary.
Agent Tesla can achieve persistence by modifying Registry key entries. Attor's dispatcher can modify the Run registry key. Kimsuky has also modified the registry entry for HKCU:\Software\Microsoft\Windows\CurrentVersion\Run registry key for persistence with the name WindowsSecurityCheck. PLAINTEE uses reg add to add a Registry Run key for persistence.
Stealth
7 techniques
Stealth
The content repeatedly describes payloads, strings, configuration files, scripts, URLs, and binaries being obfuscated or encoded using Base64, XOR, RC4, AES, RSA, hex encoding, custom algorithms, and other methods across many malware families and threat actors.
Examples throughout the content include 'encrypted payloads decrypted and executed in memory,' 'encrypts its configuration file,' 'AES-encrypted resource,' 'RC4 encrypted embedded scripts,' and 'payload includes an encrypted main component.'
The content repeatedly describes adversaries and malware injecting code, shellcode, DLLs, or payloads into legitimate processes such as svchost.exe, explorer.exe, iexplore.exe, wuauclt.exe, lsass.exe, and browser processes.
The content repeatedly describes adversaries and malware deleting files, directories, droppers, scripts, logs, archives, staged data, and other artifacts from compromised systems, e.g., 'APT29 has used SDelete to remove artifacts from victim networks' and 'Lazarus Group malware has deleted files in various ways, including "suicide scripts" to delete malware binaries from the victim.' | Several entries explicitly state files were deleted after exfiltration or upload, such as 'AppleSeed can delete files from a compromised host after they are exfiltrated,' 'Attor’s plugin deletes the collected files and log files after exfiltration,' and 'Ursnif has deleted data staged in tmp files after exfiltration.'
APT28 has performed timestomping on victim files. APT29 has used timestomping to alter the Standard Information timestamps on their web shells to match other files in the same directory. APT32 has used scheduled task raw XML with a backdated timestamp... APT38 has modified data timestamps to mimic files that are in the same folder on a compromised host.
Background Intelligent Transfer Service (BITS) is another COM-exposed Windows service that attackers use... The IBackgroundCopyJob interface is used to add files to a job, set priority, determine state, and start or stop transfers. Malware using this interface may perform payload download, staging, or exfiltration... In the example used here, the Attor plugin uses IBackgroundCopyJob to communicate with a C2 server.
Agent Tesla has created hidden folders. AppleJeus has added a leading . to plist filenames, unlisting them from the Finder app and default Terminal directory listings. APT28 has saved files with hidden file attributes. FIN13 has created hidden files and folders within a compromised Linux system /tmp directory and also used attrib.exe to hide gathered local host information.
Defense Impairment
1 technique
Defense Impairment
Discovery
5 techniques
Discovery
Multiple malware families are described as identifying/enumerating open windows or capturing foreground window titles (e.g., via EnumWindows, GetForegroundWindow, GetWindowText) to understand user activity and provide context for keylogging/screencapture.
The content repeatedly describes malware and threat actors querying, enumerating, searching, reading, or checking Windows Registry keys and values, e.g., "ADVSTORESHELL can enumerate registry keys," "APT41 queried registry values to determine items such as configured RDP ports and network configurations," and "Reg may be used to gather details from the Windows Registry of a local or remote system at the command-line interface."
The same plugin also contains COM exposed functionality for launching VBScript and PowerShell through COM client code, and through use of IWbemClassObject to enumerate installed endpoint security software.
The content repeatedly describes malware and threat actors listing files and directories, enumerating drives, searching for files by extension/name/path, retrieving file metadata, and browsing file systems (for example: "APT28 has used Forfiles to locate PDF, Excel, and Word documents during collection" and "cmd can be used to find files and directories with native functionality such as dir commands").
The content repeatedly describes malware and threat actors identifying, monitoring, or enumerating connected peripheral devices such as USB mass storage, Bluetooth devices, printers, smart card readers, cameras, Apple devices, VGA/display devices, and removable drives.
Collection
3 techniques
Collection
The content repeatedly describes adversaries and malware storing collected data, command output, credentials, archives, or files in local temporary folders, working directories, hidden directories, registry locations, recycle bins, or specific files prior to exfiltration.
Agent Tesla can steal data from the victim’s clipboard. APT38 used a Trojan called KEYLIME to collect data from the clipboard. APT39 has used tools capable of stealing contents of the clipboard.
Agrius used a custom tool, sql.net4.exe, to query SQL databases and then identify and extract personally identifiable information... AppleSeed has automatically collected data from USB drives, keystrokes, and screen images before exfiltration... Ember Bear engages in mass collection from compromised systems during intrusions.
Command and Control
5 techniques
Command and Control
AsyncRAT can proxy C2 through a Tor client. Attor has used Tor for C2 communication. Cyclops Blink has used Tor nodes for C2 traffic. GreyEnergy has used Tor relays for Command and Control servers. Siloscape uses Tor to communicate with C2. WannaCry uses Tor for command and control traffic.
During the 2025 Poland Wiper Attacks, the adversaries utilized Tor nodes for C2. APT28 has routed traffic over Tor and VPN servers to obfuscate their activities. A backdoor used by APT29 created a Tor hidden service to forward traffic from the Tor client to local ports 3389 (RDP), 139 (Netbios), and 445 (SMB) enabling full remote access from outside the network.
The content repeatedly describes malware and threat actors using SSL, TLS, HTTPS, RSA, AES, Blowfish, RC4, ECIES, Diffie-Hellman, OpenSSL, WolfSSL, and mutual TLS to protect command and control traffic.
"3PARA RAT command and control commands are encrypted within the HTTP C2 channel using the DES algorithm in CBC mode..."; "APT33 has used AES for encryption of command and control traffic."; "Carbanak encrypts the message body of HTTP traffic with RC2 (in CBC mode)."; "Duqu ... data stream can be encrypted with AES-CBC."; "PoisonIvy uses the Camellia cipher to encrypt communications."
Examples include: "encrypts some C2 with RSA", "RSA encryption for C2 communications", "hard-coded RSA public key", "RSA-2048", "RSA-4096", and "REvil has encrypted C2 communications with the ECIES algorithm". | Multiple malware families and intrusion sets are described as encrypting C2 traffic using SSL/TLS/HTTPS (e.g., "used HTTPS for command and control", "encrypts C2 communications with TLS", "uses SSL for encrypting C2 communications", "TLS-encrypted WebSocket Protocol (WSS) for C2").
Exfiltration
1 technique
Exfiltration
ADVSTORESHELL exfiltrates data over the same channel used for C2... Agrius exfiltrated staged data using tools such as Putty and WinSCP, communicating with command and control servers... numerous malware and groups sent victim data, files, credentials, or host information over existing C2 channels.
Recent activity
68 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.
Windows-based modular cyberespionage platform with plugins managed by a dispatcher component. Reported capabilities include screen capture, audio recording, keylogging, clipboard capture, file collection and upload, process/window monitoring, persistence, Tor-based C2 communications, and GSM/GPRS device fingerprinting. In the COM example, it uses BITS via IBackgroundCopyJob for C2 communications and uses COM-exposed functionality to launch VBScript and PowerShell and enumerate endpoint security software via IWbemClassObject.
Named malware/tool referenced in the content without additional description.
Malware capable of altering last-access times on files and registry keys for anti-forensics.
Malware whose dispatcher injects into running processes for privilege escalation and evasion.
The version that knows your environment.
Match every observed IP, domain, and hash against your live telemetry.
Named campaigns wielding this family, with evidence pinned to each claim.
CVEs this family uses for access and lateral movement.
YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.
Every documented technique, ranked by evidence weight.
Reddit, Mastodon, and CTI community discussion around this family.