Emerging Threathighexperimental
Kalambur Backdoor Curl TOR SOCKS Proxy Execution
Detects the execution of the "curl.exe" command, referencing "SOCKS" and ".onion" domains, which could be indicative of Kalambur backdoor activity.
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Launch
Emerging Threat
Active Threat
Developed to detect an active or emerging threat. Prioritize investigation of any alerts and correlate with threat intelligence.
Log Source
WindowsProcess Creation
ProductWindows← raw: windows
CategoryProcess Creation← raw: process_creation
Events generated when a new process is spawned on the system. Covers command-line arguments, parent/child relationships, and process metadata.
Detection Logic
Detection Logic3 selectors
detection:
selection_img:
Image|endswith: '\curl.exe'
selection_socks:
CommandLine|contains:
- 'socks5h://'
- 'socks5://'
- 'socks4a://'
selection_onion:
CommandLine|contains: '.onion'
condition: all of selection_*False Positives
Unlikely
False positives are unlikely for most environments. High confidence detection.
References
MITRE ATT&CK
Techniques
Sub-techniques
Software
Other
detection.emerging-threats
Rule Metadata
Rule ID
e99375eb-3ee0-407a-9f90-79569cc6a01c
Status
experimental
Level
high
Type
Emerging Threat
Created
Tue Feb 11
Path
rules-emerging-threats/2025/Malware/proc_creation_win_malware_kalambur_curl_socks_tor.yml
Raw Tags
attack.executionattack.command-and-controlattack.t1090attack.t1573attack.t1071.001attack.t1059.001attack.s0183detection.emerging-threats