Detection rules › Elastic
Suspicious Curl User Agent
Detects curl commands using the "cur1" user agent string, associated with BlueNoroff/Lazarus Group campaigns. This deliberate misspelling is a reliable indicator of nation-state attacks targeting cryptocurrency sectors.
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Command & Control |
Telemetry coverage
Rule body
[rule]
description = """
Detects curl commands using the "cur1" user agent string, associated with BlueNoroff/Lazarus Group campaigns. This
deliberate misspelling is a reliable indicator of nation-state attacks targeting cryptocurrency sectors.
"""
id = "e26e47b7-ec35-4060-8b35-32d01fae159e"
license = "Elastic License v2"
name = "Suspicious Curl User Agent"
os_list = ["macos"]
reference = ["https://www.huntress.com/blog/inside-bluenoroff-web3-intrusion-analysis"]
version = "1.0.3"
query = '''
process where event.type == "start" and event.action == "exec" and process.name == "curl" and
(process.args like~ "cur1-*" or process.command_line : "*cur1-*")
'''
min_endpoint_version = "8.16.0"
optional_actions = []
[[actions]]
action = "kill_process"
field = "process.entity_id"
state = 0
[[actions]]
action = "kill_process"
field = "process.parent.entity_id"
state = 0
[[threat]]
framework = "MITRE ATT&CK"
[[threat.technique]]
id = "T1105"
name = "Ingress Tool Transfer"
reference = "https://attack.mitre.org/techniques/T1105/"
[threat.tactic]
id = "TA0011"
name = "Command and Control"
reference = "https://attack.mitre.org/tactics/TA0011/"
[internal]
min_endpoint_version = "8.16.0"
Stages and Predicates
Stage 1: process
process where event.type == "start" and event.action == "exec" and process.name == "curl" and
(process.args like~ "cur1-*" or process.command_line : "*cur1-*")
Indicators
These rows show field, operator, and value matches.