YARA · SEKOIA.IO Community
SEKOIA_Downloader_Win_Curl_Agent
Detect the downloader used by Bluenoroff to install it CurlAgent
- Author
- Sekoia.io
- Date
- 2023-05-02
- Modified
- 2024-12-19
- Score / Quality
- 75 / 80
What this rule detects
Detect the downloader used by Bluenoroff to install it CurlAgent
Associated malware family: Bluenoroff.
It defines 5 patterns (5 text, 0 hex, 0 regex).
Summary generated from the rule's metadata and condition.
Rule source
downloader-win-curl-agent.yarDetection Rule License 1.1
rule SEKOIA_Downloader_Win_Curl_Agent
{
meta:
= "Detect the downloader used by Bluenoroff to install it CurlAgent"
= "Sekoia.io"
= "ddeb2d8f-1b10-4a33-b768-d19412e8551a"
= "2023-05-02"
= "2024-12-19"
= "https://github.com/SEKOIA-IO/Community"
= "https://github.com/SEKOIA-IO/Community/blob/a438a5901a211c2abdf75da9c93921ef187473d1/yara_rules/downloader_win_curl_agent.yar#L1-L19"
= "https://github.com/SEKOIA-IO/Community/blob/a438a5901a211c2abdf75da9c93921ef187473d1/LICENSE.md"
= "b34375ec051c969adec82901c1130b0a389261912559d70c652ee826cb2d4107"
= 75
= 80
= ""
= "1.0"
= "TLP:CLEAR"
strings:
$ = "%s\\marcoor.dll" wide
$ = "curl -A cur1-agent -L %s -s -d dl"
$ = "curl -A cur1-agent -L %s -s -d da"
$ = "cmd /c timeout /t 10 & rundll32 \"%s\" #1" wide
$ = "cmd /c timeout /t 10 & Del /f /q \"%s\" & attrib -s -h \"%s\" & rundll32 \"%s\" #1" wide
condition:
3 of them
}
Strings (5 patterns)
| Identifier | Type | Value | Modifiers |
|---|---|---|---|
| $ | text | "%s\\marcoor.dll" | wide |
| $ | text | "curl -A cur1-agent -L %s -s -d dl" | |
| $ | text | "curl -A cur1-agent -L %s -s -d da" | |
| $ | text | "cmd /c timeout /t 10 & rundll32 \"%s\" #1" | wide |
| $ | text | "cmd /c timeout /t 10 & Del /f /q \"%s\" & attrib -s -h \"%s\" & rundll32 \"%s\" #1" | wide |
Condition
3 of themIn plain words (Heuristic)
- At least 3 patterns in the rule 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.
Drop a file here or click to chooseScanned locally with YARA-X. Files up to 200 MB.
References
Licence & attribution
Author: Sekoia.io
Source repository: SEKOIA.IO Community @ a438a5901a
Licence: Detection Rule License 1.1 (repository licence)
Mirrored via YARA Forge 20260927, which prefixes rule names with the source and adds normalised meta fields.
Rule id: ddeb2d8f-1b10-4a33-b768-d19412e8551a
Metadata
| version | 1.0 |
|---|---|
| classification | TLP:CLEAR |
Related rules
- MalwareMalpedia signator rules· Felix Bilstein - yara-signator at cocacoding dot com· 2026-05-04
- MalwareSEKOIA.IO Community· Sekoia.io· 2024-07-16
- MalwareSEKOIA.IO Community· Sekoia.io· 2024-08-23
- MalwareSEKOIA.IO Community· Sekoia.io· 2024-04-22
- MalwareSEKOIA.IO Community· Sekoia.io· 2024-07-23
- MalwareSEKOIA.IO Community· Sekoia.io· 2024-10-20
- MalwareSEKOIA.IO Community· Sekoia.io· 2024-03-20
- MalwareSEKOIA.IO Community· Sekoia.io· 2024-03-20