frack113
27 lines
708 B
YAML
27 lines
708 B
YAML
title: Suspicious User Agent
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id: 894a8613-cf12-48b3-8e57-9085f54aa0c3
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status: experimental
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description: Detects suspicious User Agent strings that end with an equal sign, which can be a sign of base64 encoded values used as User Agent string
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references:
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- https://blogs.jpcert.or.jp/en/2022/07/yamabot.html
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author: Florian Roth
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date: 2022/07/08
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tags:
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- attack.command_and_control
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- attack.t1071.001
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logsource:
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category: proxy
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detection:
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selection:
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c-useragent|endswith:
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- '='
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- 'TW96aWxsY' # base64 encoded Mozilla/ as used by YamaBot
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condition: selection
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fields:
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- ClientIP
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- c-uri
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- c-useragent
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falsepositives:
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- Unknown
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level: high
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