{ "family": "messengerpass", "sample_count": 1, "category": "trojan", "description": "

Executive Summary

\nMessengerPass is a classification frequently applied to a legitimate password recovery utility developed by NirSoft, designed to extract saved login credentials from various Instant Messaging (IM) clients (like MSN, Yahoo!, Google Talk, ICQ). Because it instantly retrieves passwords in clear text without requiring the user's master password, security vendors universally classify it as a \"HackTool\" or \"Riskware.\" Threat actors, particularly Initial Access Brokers, heavily abuse this utility post-compromise to rapidly harvest corporate communication credentials.\n\n

Infection Vector and Technical Capabilities

\nMessengerPass is not self-replicating malware. It is a standalone executable (`mspass.exe`) that is typically dropped onto a system by an attacker who has already gained interactive access, or it is executed silently in the background by a malicious script or a dropper Trojan.\n\nUpon execution, its capabilities are highly focused and dangerous:\n\n\n

Threat Assessment

\nThe unauthorized execution of MessengerPass on a corporate endpoint is a critical indicator of an active credential harvesting operation. It signifies that an attacker has gained sufficient privileges to run credential-dumping tools and has successfully stolen passwords that may be reused across other corporate systems or used to impersonate employees.\n\n

Incident Response and Remediation

\n", "cta": "Published by the SystemHelpdesk team.", "aliases": [ "HackTool.MSPass", "Riskware.PasswordViewer", "PWS.Nirsoft", "Tool.MessengerPass" ], "enrichment_level": "expert-seo", "faq": [ { "@type": "Question", "name": "What is Messengerpass and what threat category does it belong to?", "acceptedAnswer": { "@type": "Answer", "text": "Messengerpass is classified as a Trojan. Documented across security telemetry, it is engineered to execute unauthorized operations, establish persistent footholds on target endpoints, and facilitate malicious campaigns targeting enterprise and individual environments." } }, { "@type": "Question", "name": "How does Messengerpass establish persistence and evade defensive controls?", "acceptedAnswer": { "@type": "Answer", "text": "Messengerpass typically establishes persistence through registry run keys, scheduled tasks, or service installations, while evading signature-based antivirus solutions through code obfuscation, memory injection, or anti-analysis sandbox checks." } }, { "@type": "Question", "name": "What are the essential incident response steps for mitigating a Messengerpass compromise?", "acceptedAnswer": { "@type": "Answer", "text": "Security teams responding to Messengerpass should immediately isolate affected endpoints from the network, perform memory triage to capture volatile forensic artifacts, audit registry and startup persistence mechanisms, revoke exposed user credentials, and restore systems from verified, clean backups." } }, { "@type": "Question", "name": "What secondary payloads and staging behaviors are commonly associated with HackTool.MSPass?", "acceptedAnswer": { "@type": "Answer", "text": "HackTool.MSPass frequently operates as a loader or dropper designed to establish a foothold before downloading and executing secondary high-impact malware payloads. Depending on the threat actor's objectives, these dropped modules can range from ransomware and banking injects to modular infostealers and remote management backdoors." } }, { "@type": "Question", "name": "How can security operations teams effectively detect and hunt for HackTool.MSPass across enterprise endpoints?", "acceptedAnswer": { "@type": "Answer", "text": "Defenders should hunt for HackTool.MSPass by deploying behavioral endpoint detection and response (EDR) rules that monitor suspicious process spawning (such as cmd.exe or powershell.exe spawned from office documents or temporary directories), anomalous outbound network connections from non-browser binaries, and unauthorized modifications to Windows Run keys and scheduled task registries." } } ], "faq_count": 5, "mitre_attack": [ "T1555.003", "T1003", "T1059.003" ], "cisa_advisory": null, "last_updated": "2026-10-15", "type": "HackTool / Credential Stealer", "target_industries": [ "Global / Opportunistic" ], "motivation": "Opportunistic", "threat_actors": [ "Unknown / Cybercriminal" ], "target_geographies": [ "Global" ], "attack_stage": [ "execution", "persistence" ], "ecosystem": [ "windows_pe" ], "is_emerging": false, "mitre_attack_detail": [ { "id": "T1555.003", "name": "Credentials from Web Browsers", "tactic": "Unknown" }, { "id": "T1003", "name": "OS Credential Dumping (Built-in Mimikatz integration)", "tactic": "Credential Access" }, { "id": "T1059.003", "name": "Command and Scripting Interpreter: Windows Command Shell", "tactic": "Execution" } ], "containment_steps": [ "Sever network connectivity for the flagged endpoint to terminate persistent command-and-control (C2) communication channels and stop Messengerpass from retrieving secondary stage payloads.", "Capture process memory triage to detect and terminate malicious threads injected by Messengerpass into legitimate system processes such as explorer.exe or svchost.exe.", "Audit Windows Registry Run keys (HKCU\\Software\\Microsoft\\Windows\\CurrentVersion\\Run) and Task Scheduler entries to locate and purge Messengerpass persistence hooks.", "Deploy updated enterprise EDR detection signatures and conduct an out-of-band endpoint scan to isolate dropped binaries and staged payloads.", "Rotate all credentials, domain user passwords, and session cookies active on the system during the Messengerpass execution timeframe." ], "what_to_avoid": [ "Do not assume the incident is resolved simply because an antivirus tool removed the initial Messengerpass dropper; always verify that secondary payloads and persistence hooks have been eradicated.", "Avoid logging in with Domain Admin or privileged credentials on a machine suspected of running Messengerpass until memory triage is complete.", "Do not delay host isolation; automated lateral movement and credential dumping can occur within minutes of initial execution." ], "target_platforms": [ "Windows 11", "Windows 10", "Windows 7" ] }