subssetup.exe

yearsoft

This is the installer/setup program for a Yontoo adware component, a web browser plugin that injects unwanted ads in the browser. The application subssetup.exe by yearsoft has been detected as adware by 1 anti-malware scanner with very strong indications that the file is a potential threat. The program is a setup application that uses the NSIS (Nullsoft Scriptable Install System) installer. It is also typically executed from the user's temporary directory. While running, it connects to the Internet address api.yontoo.com on port 80 using the HTTP protocol.
Publisher:
yearsoft  (signed and verified)

Product:
yearsoft

Description:
SubShop

Version:
3.0.0.4

MD5:
2148b8c2cecdbe017495268abe3794f4

SHA-1:
2d978e5f7f6b60229ec90353fd29f3382c39dcce

SHA-256:
80a20d63d421229177b624da13486a009659b0ac087929e9cdd8db7a5a78d7c4

Scanner detections:
1 / 68

Status:
Adware

Explanation:
Belongs to the Sambreel/Yontoo progam that inserts various forms of advertising in the user's web browser, installed with minimal or no user consent.

Analysis date:
11/19/2025 6:35:35 AM UTC  (today)

Scan engine
Detection
Engine version

Reason Heuristics
PUP.Yontoo (M)
17.1.17.19

File size:
1 MB (1,069,968 bytes)

Product version:
3.0.0.4

Copyright:
Copyright yearsoft

File type:
Executable application (Win32 EXE)

Installer:
NSIS (Nullsoft Scriptable Install System)

Common path:
C:\users\{user}\appdata\local\temp\subssetup.exe

Digital Signature
Signed by:

Authority:
Thawte, Inc.

Valid from:
6/21/2013 9:00:00 AM

Valid to:
6/22/2014 8:59:59 AM

Subject:
CN=yearsoft, OU=IT Team, O=yearsoft, L=Ansan-si, S=Gyeonggi-do, C=KR

Issuer:
CN=Thawte Code Signing CA - G2, O="Thawte, Inc.", C=US

Serial number:
1D640099747B7B0113E4E8A226D9C798

File PE Metadata
Compilation timestamp:
6/7/2009 6:41:59 AM

OS version:
4.0

OS bitness:
Win32

Subsystem:
Windows GUI

Linker version:
6.0

Entry address:
0x30FA

Entry point:
81, EC, 80, 01, 00, 00, 53, 55, 56, 33, DB, 57, 89, 5C, 24, 18, C7, 44, 24, 10, 60, 91, 40, 00, 33, F6, C6, 44, 24, 14, 20, FF, 15, 30, 70, 40, 00, 68, 01, 80, 00, 00, FF, 15, B0, 70, 40, 00, 53, FF, 15, 7C, 72, 40, 00, 6A, 08, A3, 18, EC, 42, 00, E8, F1, 2B, 00, 00, A3, 64, EB, 42, 00, 53, 8D, 44, 24, 34, 68, 60, 01, 00, 00, 50, 53, 68, 98, 8F, 42, 00, FF, 15, 58, 71, 40, 00, 68, 54, 91, 40, 00, 68, 60, E3, 42, 00, E8, A4, 28, 00, 00, FF, 15, AC, 70, 40, 00, BF, 00, 40, 43, 00, 50, 57, E8, 92, 28, 00, 00...
 
[+]

Entropy:
7.9892

Packer / compiler:
Nullsoft install system v2.x

Code size:
23.5 KB (24,064 bytes)

The executing file has been seen to make the following network communications in live environments.

TCP (HTTP):
Connects to wac.edgecastcdn.net  (72.21.81.13:80)

TCP (HTTP):
Connects to service.yontoo.com  (8.25.35.148:80)

TCP (HTTP):
Connects to api.yontoo.com  (8.25.35.15:80)

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