Concrete signature match: Password Stealer - Steals credentials and sensitive information for .NET (Microsoft Intermediate Language) platform, family Polazert
PWS:MSIL/Polazert!rfn is a confirmed .NET-based credential stealer designed to exfiltrate sensitive data, including browser form history and login credentials, and potentially RDP information. It establishes persistence and evades detection using various system utilities like rundll32, powershell, BITS jobs, and scheduled tasks.
Relevant strings associated with this threat:
- Win32_ComputerSystem.Name='{0}' (PEHSTR_EXT)
- GetComputerName (PEHSTR_EXT)
- http:// (PEHSTR_EXT)
- *.rdp (PEHSTR_EXT)
- \default.rdp (PEHSTR_EXT)
- formhistory.sqlite (PEHSTR_EXT)
- logins.json (PEHSTR_EXT)
- deimos.dll (PEHSTR_EXT)
- HttpWebResponse (PEHSTR_EXT)
- HttpStatusCode (PEHSTR_EXT)
- System.Text (PEHSTR_EXT)
- !#HSTR:StringCodeForMshta.A!pli (PEHSTR_EXT)
- !#HSTR:StringCodeForHooking.C!pli (PEHSTR_EXT)
- !#HSTR:StringCodeForHooking.D!pli (PEHSTR_EXT)
- !#HSTR:StringCodeForHooking.L!pli (PEHSTR_EXT)
- !#HSTR:StringCodeForHooking.O!pli (PEHSTR_EXT)
- !#HSTR:StringCodeForRegsvr32.A!pli (PEHSTR_EXT)
- !#HSTR:StringCodeForRundll32.A!pli (PEHSTR_EXT)
- rundll32 (PEHSTR_EXT)
- !#HSTR:StringCodeForBITSJobs.A!pli (PEHSTR_EXT)
- !#HSTR:StringCodeForPowerShell.G!pli (PEHSTR_EXT)
- !#HSTR:StringCodeForScheduledTask.A!pli (PEHSTR_EXT)
- !#HSTR:StringCodeForDataEncoding.D!pli (PEHSTR_EXT)
- !#HSTR:StringCodeForHooking.J!pli (PEHSTR_EXT)
- !#HSTR:StringCodeForHooking.K!pli (PEHSTR_EXT)
- !#HSTR:StringCodeForRemoteFileCopy.B!pli (PEHSTR_EXT)
- !#HSTR:ExecutionGuardrails (PEHSTR_EXT)
- !#HSTR:StringCodeForFileDeletion.A!pli (PEHSTR_EXT)
- !#HSTR:StringCodeForHooking.M!pli (PEHSTR_EXT)
- !#HSTR:StringCodeForNetshHelperDLL.A!pli (PEHSTR_EXT)
- !#HSTR:StringCodeForRemoteServices.A!pli (PEHSTR_EXT)a0e2ed2550ed0bf5b27295fb6252dbec216a70342380705f2f74f88445e0a486Immediately isolate the infected system, remove the detected malware, and force password resets for all accounts used on the device. Conduct a comprehensive system scan to identify and eliminate any remaining malicious components or persistence mechanisms, and monitor network activity for C2 communication.