Smsspy

Overview

TrojanSpy:AndroidOS/Smsspy (or Win32 variants targeting mobile emulators/connected devices) is a specialized spyware focused entirely on intercepting and exfiltrating Short Message Service (SMS) data (`T1114.001`). Its primary, critical function is to bypass Multi-Factor Authentication (MFA) by silently reading the One-Time Passwords (OTPs) sent by banks during fraudulent transactions.

Understanding Smsspy (2FA Interceptors)
To an end-user, the infection is often unnoticed until they receive a notification of a cleared bank account. The SMS messages containing the authentication codes are often hidden from the user's inbox by the malware. For security teams, Smsspy highlights the inherent weakness of SMS-based 2FA against targeted banking attacks.

Execution and Interception Mechanics
Smsspy is typically distributed via third-party app stores, deceptive 'security update' SMS links (Smishing), or dropped by a primary banking trojan. Once installed, it requests the `READ_SMS` and `RECEIVE_SMS` Android permissions (`T1624`). It then establishes a background service to monitor all incoming messages. When a message arrives matching specific regex patterns (e.g., containing 'code', 'OTP', or originating from known bank shortcodes), it immediately exfiltrates the contents via HTTP/HTTPS to the attacker's C2 server (`T1041`), often deleting or marking the message as read locally to hide the activity from the victim.

Indicators of Compromise & Impact
The impact is the total compromise of SMS-based MFA and potential severe financial loss. IoCs include unexpected apps possessing SMS-reading permissions, rapid battery drain, and network logs showing background HTTP POST requests immediately following the receipt of an SMS message.

MITRE ATT&CK Techniques

Observed techniques used by this family, mapped to the MITRE ATT&CK framework:

Generated Detections (Boilerplate)

These YARA and Sigma rules are auto-generated based on the family name and aliases. They must be heavily tuned before deployment in a production environment.

YARA Rule

rule MALWARE_WIN_SMSSPY {
    meta:
        description = "Detects Smsspy (trojan)"
        author = "SystemHelpdesk Boilerplate Generator"
        date = "2026-07-06"
    strings:
        $s1 = "smsspy" ascii wide nocase
    condition:
        uint16(0) == 0x5a4d and any of them
}

Sigma Rule

title: Suspicious Smsspy Activity
id: 052f58b230d999d87b89bcafe32cba1b
status: experimental
description: Detects generic indicators of the smsspy malware family.
logsource:
    category: process_creation
    product: windows
detection:
    selection:
        Image|endswith:
            - '\cmd.exe'
            - '\powershell.exe'
        CommandLine|contains:
            - "*smsspy*"
    condition: selection
level: medium

Containment & Response Steps

Ordered checklist for responders. Adapt to your environment and engage professional support for active incidents.

1. Immediately disable the device's cellular connection (turn on Airplane Mode) to prevent further SMS interception and exfiltration.
2. Contact financial institutions immediately to freeze accounts and report that SMS-based 2FA has been compromised.
3. Identify and uninstall the malicious application granting itself SMS permissions (check Settings -> Apps -> Permissions).
4. Transition all critical accounts from SMS-based 2FA to app-based authenticators (like Google Authenticator) or hardware keys (YubiKey).

What to Avoid

Common mistakes during response to this family that can destroy evidence, spread the infection, or worsen recovery.

1. Do not assume a transaction is safe just because SMS 2FA is enabled; Smsspy exists specifically to defeat this mechanism.
2. Avoid downloading applications from outside official app stores, as this is the primary delivery method for mobile spyware.

References & External Analysis

• Search "smsspy" on VirusTotal (External Analysis)

Frequently Asked Questions

Related Families (Category: trojan)

Explore other malware families in the same category:

• Enfal
• Browserpwdstealer
• Cridex
• Arkeistealer
• Dynamer

Machine-readable

Get this profile as JSON: https://jordan123234-malware-families-explorer.static.hf.space/api/smsspy.json

Ecosystem & Interactive Environments

This profile is part of the Malware Families Catalog, a public dataset of 2,899 malware families. The catalog is also published across our ecosystem: Hugging Face, Kaggle, Zenodo, Replit, StackBlitz, CodeSandbox, and CodePen.