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/*
This Yara ruleset is under the GNU-GPLv2 license (http://www.gnu.org/licenses/gpl-2.0.html) and open to any user or organization, as long as you use it under this license.
*/
/*
Generic Cloaking
Florian Roth
BSK Consulting GmbH
License: Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0)
Copyright and related rights waived via https://creativecommons.org/licenses/by-nc-sa/4.0/
*/
rule Binary_Drop_Certutil {
meta:
description = "Drop binary as base64 encoded cert trick"
author = "Florian Roth"
reference = "https://goo.gl/9DNn8q"
date = "2015-07-15"
score = 70
strings:
$s0 = "echo -----BEGIN CERTIFICATE----- >" ascii
$s1 = "echo -----END CERTIFICATE----- >>" ascii
$s2 = "certutil -decode " ascii
condition:
filesize < 10KB and all of them
}
rule StegoKatz {
meta:
description = "Encoded Mimikatz in other file types"
author = "Florian Roth"
reference = "https://goo.gl/jWPBBY"
date = "2015-09-11"
score = 70
strings:
$s1 = "VC92Ny9TSXZMNk5jLy8vOUlqUTFVRlFNQTZMLysvdjlJaTh2L0ZUNXJBUUJJaTFRa1NFaUx6K2hWSS8vL1NJME44bklCQU9pZC92Ny9USTJjSkpBQUFBQXp3RW1MV3hCSmkyc1lTWXR6S0VtTDQxL0R6TXhNaTl4SmlWc0lUWWxMSUUySlF4aFZWbGRCVkVGVlFWWkJWMGlCN1BBQUFBQklnMlFrYUFDNE1BQUFBRW1MNkVTTmNPQ0pSQ1JnaVVRa1pFbU5RN0JKaTlsTWpRWFBGQU1BU0ls" ascii
$s2 = "Rpd3ovN3FlalVtNklLQ0xNNGtOV1BiY0VOVHROT0Zud25CWGN0WS9BcEdMR28rK01OWm85Nm9xMlNnY1U5aTgrSTBvNkFob1FOTzRHQWdtUElEVmlqald0Tk90b2FmN01ESWJUQkF5T0pYbTB4bFVHRTBZWEFWOXVoNHBkQnRrS0VFWWVBSEE2TDFzU0c5a2ZFTEc3QWd4WTBYY1l3ZzB6QUFXS09JZE9wQVhEK3lnS3lsR3B5Q1ljR1NJdFNseGZKWUlVVkNFdEZPVjRJUldERUl1QXpKZ2pCQWdsd0Va" ascii
condition:
filesize < 1000KB and 1 of them
}