Malicious FrostyNeighbor ViberPC Renamed Rundll32 DLL Execution

ATT&CK techniques

Defense Evasion

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
- T1036.005Match Legitimate Resource Name or Location
- T1218.011Rundll32
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects a rundll32 copy renamed to ViberPC.exe loading ViberPC.dll and invoking its SettingTimeAPI export, the execution chain used by the FrostyNeighbor PicassoLoader campaign. Renaming rundll32 and the payload to imitate the Viber messenger disguises DLL proxy execution as a trusted application.

Reporting behind it

Related detections9 linkedT1218.011 — drag to rearrange

FalseFont Masqueraded System Binary Execution from User Profile Directory (via process_creation)

Malicious Rundll32 RunHTMLApplication Remote Execution

Suspicious Execution of ELF Masquerading as Build Artifact

Suspicious Rundll32 Execution of PhotoViewer.dll ImageView_Fullscreen (via process_creation)

Malicious IcedID Loader Execution via Rundll32 from Excel Macro (via process_creation)

Malicious SolarWinds BusinessLayerHost Spawning Suspicious Child Process (SUNBURST) (via process_creation)

Suspicious Rundll32 Execution of DLL Masquerading as Text File via Blind Eagle (via process_creation)

Suspicious Rundll32 Spawning Injection Target Process via Qakbot (via process_creation)

Malicious Lunar Spider Loader Execution via rundll32 (via process_creation)

Malicious FrostyNeighbor ViberPC Renamed Rundll32 DLL Execution

Pivot detection · T1218.011 · 9 related

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.

Full detection rule

Unlock this rule to view and copy it

The detection logic is included with a plan. Everything else — context, mappings and implementation details — stays free on this page.

Sign in for 3 free unlocks

Signing in gives you 3 unlocks to spend on any rule in the library. No card, and they do not expire.

Also included

Unlocked rules convert on this page — to Splunk SPL or Splunk — Raw Index SPL or Microsoft Sentinel KQL or Microsoft Sentinel ASIM ASIM KQL or Microsoft Defender XDR KQL or Elastic Security KQL or Elastic Security Lucene or Elastic Security ES|QL or CrowdStrike Falcon CQL or SentinelOne PowerQuery or Palo Alto Cortex XDR XQL or Carbon Black Cloud Platform Search or Carbon Black EDR Process Search or Google Security Operations UDM Search or IBM QRadar AQL or Sumo Logic Cloud SIEM Rules expression or Rapid7 InsightIDR LEQL or Graylog Search or OpenSearch Lucene or OpenSearch PPL PPL or Grafana Loki LogQL or SQLite SQL or Zircolite SQLite — with the log-source profile the engine picked, the field map it used, and everything it could not express. Converting a rule you have unlocked costs no further credit.

See it run on a free rule →Convert your own rule →