YARA · Volexity threat-intel
VOLEXITY_Malware_Win_Cobaltstrike_D
The CobaltStrike malware family, variant D.
- Author
- threatintel@volexity.com
- Date
- 2021-05-25
- Modified
- 2024-11-22
- Score / Quality
- 75 / 80
What this rule detects
The CobaltStrike malware family, variant D.
Associated malware family: Cobalt Strike.
It defines 7 patterns (6 text, 1 hex, 0 regex).
Summary generated from the rule's metadata and condition.
Rule source
rule VOLEXITY_Malware_Win_Cobaltstrike_D : FILE MEMORY
{
meta:
= "The CobaltStrike malware family, variant D."
= "threatintel@volexity.com"
= "89a2459b-314b-513e-bd1a-8c4239a30338"
= "2021-05-25"
= "2024-11-22"
= "https://github.com/volexity/threat-intel"
= "https://github.com/volexity/threat-intel/blob/3a9d0b52459877ee866a9a0ba06e60059b778c77/2021/2021-05-27 - Suspected APT29 Operation Launches Election Fraud Themed Phishing Campaigns/indicators/yara.yar#L27-L54"
= "https://github.com/volexity/threat-intel/blob/3a9d0b52459877ee866a9a0ba06e60059b778c77/LICENSE.txt"
= "b041efb8ba2a88a3d172f480efa098d72eef13e42af6aa5fb838e6ccab500a7c"
= "751b6832f2952d369cb616b28ac009d7bfcc4d92bf2db36d87d69bc1e9fa6c75"
= 75
= 80
= "FILE, MEMORY"
= "win"
= "all"
= "file,memory"
= "critical"
= "See license at https://github.com/volexity/threat-intel/blob/main/LICENSE.txt"
= 5445
= 5
strings:
$s1 = "%s (admin)" fullword
$s2 = {48 54 54 50 2F 31 2E 31 20 32 30 30 20 4F 4B 0D 0A 43 6F 6E 74 65 6E 74 2D 54 79 70 65 3A 20 61 70 70 6C 69 63 61 74 69 6F 6E 2F 6F 63 74 65 74 2D 73 74 72 65 61 6D 0D 0A 43 6F 6E 74 65 6E 74 2D 4C 65 6E 67 74 68 3A 20 25 64 0D 0A 0D 0A 00}
$s3 = "%02d/%02d/%02d %02d:%02d:%02d" fullword
$s4 = "%s as %s\\%s: %d" fullword
$s5 = "%s&%s=%s" fullword
$s6 = "rijndael" fullword
$s7 = "(null)"
condition:
6 of ( $s* )
}
Strings (7 patterns)
| Identifier | Type | Value | Modifiers |
|---|---|---|---|
| $s1 | text | "%s (admin)" | fullword |
| $s2 | hex | {48 54 54 50 2F 31 2E 31 20 32 30 30 20 4F 4B 0D 0A 43 6F 6E 74 65 6E 74 2D 54 79 70 65 3A 20 61 70 70 6C 69 63 61 74 69 6F 6E 2F 6F 63 74 65 74 2D 73 74 72 65 … | |
| $s3 | text | "%02d/%02d/%02d %02d:%02d:%02d" | fullword |
| $s4 | text | "%s as %s\\%s: %d" | fullword |
| $s5 | text | "%s&%s=%s" | fullword |
| $s6 | text | "rijndael" | fullword |
| $s7 | text | "(null)" |
Condition
6 of ( $s* )In plain words (Heuristic)
- At least 6 patterns in ( $s* ) must match.
Test this rule in your browser
Drop a file to scan it with this rule using YARA-X compiled to WebAssembly. Nothing is uploaded.
References
Sample hashes
Hashes of samples the author lists in the rule's meta (look them up in your threat-intelligence platform).
- b041efb8ba2a88a3d172f480efa098d72eef13e42af6aa5fb838e6ccab500a7c
Licence & attribution
Author: threatintel@volexity.com
Source repository: Volexity threat-intel @ 3a9d0b5245
Licence: BSD 2-Clause License (stated in the rule's own meta)
“See license at https://github.com/volexity/threat-intel/blob/main/LICENSE.txt”
Copyright notice: Copyright 2022 by Volexity, Inc.
Mirrored via YARA Forge 20260927, which prefixes rule names with the source and adds normalised meta fields.
Rule id: 89a2459b-314b-513e-bd1a-8c4239a30338
Metadata
| os | win |
|---|---|
| os_arch | all |
| scan_context | file,memory |
| severity | critical |
| rule_id | 5445 |
| version | 5 |
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