MalwareBazaar Database

You are currently viewing the MalwareBazaar entry for SHA256 25f0b776a5fa4bbf0f0727207cdcf58b3f883d2f0e210556350d050b427e69d4. While MalwareBazaar tries to identify whether the sample provided is malicious or not, there is no guarantee that a sample in MalwareBazaar is malicious.

Database Entry



Efimer


Vendor detections: 10


Intelligence 10 IOCs YARA 7 File information Comments

SHA256 hash: 25f0b776a5fa4bbf0f0727207cdcf58b3f883d2f0e210556350d050b427e69d4
SHA3-384 hash: 40f4dc1554875b24bf7205fdc976b24f731b9ce20399083bf9e4d92fc7101ecf8785cf55ea21b7d723021d6a89731e99
SHA1 hash: cff5e73dac39d69216ae96b95134373ff5ffc418
MD5 hash: 0c193f0e39efbab65b8ab5dbd6bdb7e2
humanhash: salami-speaker-tango-quiet
File name:default.dat
Download: download sample
Signature Efimer
File size:14'295'853 bytes
First seen:2026-07-13 09:52:10 UTC
Last seen:Never
File type:Executable exe
MIME type:application/x-dosexec
imphash dcaf48c1f10b0efa0a4472200f3850ed (283 x Efimer, 60 x BlankGrabber, 22 x NetSupport)
ssdeep 393216:IwbMVk9f8Qf/A6DXMCHWUjXhcuI3/PGTAI:IFo9XMb8X2H/O7
TLSH T12BE6335859C022EEE6D3527CAEE1855EE5B9B8B64B31CD8B4778C3B57C471E08878383
TrID 37.0% (.EXE) Win64 Executable (generic) (6522/11/2)
28.6% (.EXE) Win16 NE executable (generic) (5038/12/1)
11.5% (.EXE) OS/2 Executable (generic) (2029/13)
11.3% (.EXE) Generic Win/DOS Executable (2002/3)
11.3% (.EXE) DOS Executable (generic) (2000/1)
Magika pebin
dhash icon b271e8cccce8f0b2 (2 x Efimer)
Reporter aachum
Tags:ClickFix Efimer exe


Avatar
iamaachum
https://tuasesoriadigital.es/default.dat

Intelligence


File Origin
# of uploads :
1
# of downloads :
173
Origin country :
ES ES
Vendor Threat Intelligence
Malware configuration found for:
PyInstaller
Details
Verdict:
Malicious
Score:
97.4%
Tags:
installer shell sage
Result
Verdict:
Clean
Maliciousness:

Behaviour
Creating a file in the %temp% subdirectories
Restart of the analyzed sample
Creating a window
Gathering data
Verdict:
Malicious
File Type:
exe x64
First seen:
2026-07-13T07:10:00Z UTC
Last seen:
2026-07-14T08:35:00Z UTC
Hits:
~10
Result
Threat name:
n/a
Detection:
malicious
Classification:
evad
Score:
72 / 100
Signature
Adds a directory exclusion to Windows Defender
Found pyInstaller with non standard icon
Joe Sandbox ML detected suspicious sample
Loading BitLocker PowerShell Module
Multi AV Scanner detection for submitted file
Sigma detected: Powershell Base64 Encoded MpPreference Cmdlet
Sigma detected: Suspicious Script Execution From Temp Folder
Behaviour
Behavior Graph:
behaviorgraph top1 signatures2 2 Behavior Graph ID: 1941421 Sample: default.dat.exe Startdate: 13/07/2026 Architecture: WINDOWS Score: 72 56 Multi AV Scanner detection for submitted file 2->56 58 Joe Sandbox ML detected suspicious sample 2->58 60 Sigma detected: Powershell Base64 Encoded MpPreference Cmdlet 2->60 62 Sigma detected: Suspicious Script Execution From Temp Folder 2->62 8 default.dat.exe 31 2->8         started        12 svchost.exe 1 1 2->12         started        process3 dnsIp4 46 C:\Users\user\AppData\...\unicodedata.pyd, PE32+ 8->46 dropped 48 C:\Users\user\AppData\Local\...\select.pyd, PE32+ 8->48 dropped 50 C:\Users\user\AppData\Local\...\python313.dll, PE32+ 8->50 dropped 52 16 other files (none is malicious) 8->52 dropped 66 Adds a directory exclusion to Windows Defender 8->66 68 Found pyInstaller with non standard icon 8->68 15 default.dat.exe 1 8->15         started        54 127.0.0.1 unknown unknown 12->54 file5 signatures6 process7 signatures8 72 Adds a directory exclusion to Windows Defender 15->72 18 cmd.exe 1 15->18         started        21 cmd.exe 1 15->21         started        23 cmd.exe 1 15->23         started        25 9 other processes 15->25 process9 signatures10 64 Adds a directory exclusion to Windows Defender 18->64 27 powershell.exe 23 18->27         started        30 conhost.exe 18->30         started        32 powershell.exe 23 21->32         started        34 conhost.exe 21->34         started        36 powershell.exe 23 23->36         started        38 conhost.exe 23->38         started        40 powershell.exe 25->40         started        42 powershell.exe 25->42         started        44 16 other processes 25->44 process11 signatures12 70 Loading BitLocker PowerShell Module 36->70
Verdict:
inconclusive
YARA:
5 match(es)
Tags:
Executable PDB Path PE (Portable Executable) PE File Layout Win 64 Exe x64
Threat name:
Win64.Trojan.Yogi
Status:
Malicious
First seen:
2026-07-13 09:53:40 UTC
File Type:
PE+ (Exe)
Extracted files:
482
AV detection:
6 of 24 (25.00%)
Threat level:
  5/5
Result
Malware family:
n/a
Score:
  8/10
Tags:
execution pyarmor pyinstaller
Behaviour
Suspicious behavior: EnumeratesProcesses
Suspicious use of AdjustPrivilegeToken
Suspicious use of WriteProcessMemory
Loads dropped DLL
Command and Scripting Interpreter: PowerShell
Unpacked files
SH256 hash:
25f0b776a5fa4bbf0f0727207cdcf58b3f883d2f0e210556350d050b427e69d4
MD5 hash:
0c193f0e39efbab65b8ab5dbd6bdb7e2
SHA1 hash:
cff5e73dac39d69216ae96b95134373ff5ffc418
SH256 hash:
36585912e5eaf83ba9fea0631534f690ccdc2d7ba91537166fe53e56c221e153
MD5 hash:
862f820c3251e4ca6fc0ac00e4092239
SHA1 hash:
ef96d84b253041b090c243594f90938e9a487a9a
SH256 hash:
a5c6a329698490a035133433928d04368ce6285bb91a9d074fc285de4c9a32a4
MD5 hash:
16855ebef31c5b1ebe767f1c617645b3
SHA1 hash:
315521f3a748abfa35cd4d48e8dd09d0556d989b
SH256 hash:
e87c33138805cecce647992220cf832a408ebcd470c1a723cd3e1b36b52eeaa5
MD5 hash:
4b1b7a334a4b23e04f0c966569e89158
SHA1 hash:
3552f7fde8ff7498ed144030a684f6d5d92dead9
Please note that we are no longer able to provide a coverage score for Virus Total.

YARA Signatures


MalwareBazaar uses YARA rules from several public and non-public repositories, such as YARAhub and Malpedia. Those are being matched against malware samples uploaded to MalwareBazaar as well as against any suspicious process dumps they may create. Please note that only results from TLP:CLEAR rules are being displayed.

Rule name:DebuggerCheck__API
Reference:https://github.com/naxonez/yaraRules/blob/master/AntiDebugging.yara
Rule name:DebuggerException__SetConsoleCtrl
Reference:https://github.com/naxonez/yaraRules/blob/master/AntiDebugging.yara
Rule name:Detect_PyInstaller
Author:Obscurity Labs LLC
Description:Detects PyInstaller compiled executables across platforms
Rule name:golang_bin_JCorn_CSC846
Author:Justin Cornwell
Description:CSC-846 Golang detection ruleset
Rule name:PyInstaller
Author:@bartblaze
Description:Identifies executable converted using PyInstaller. This rule by itself does NOT necessarily mean the detected file is malicious.
Rule name:TH_AntiVM_MassHunt_Win_Malware_2026_CYFARE
Author:CYFARE
Description:Detects Windows malware employing anti-VM / anti-sandbox evasion techniques across VMware, VirtualBox, Hyper-V, QEMU, Xen, and generic sandbox environments
Reference:https://cyfare.net/
Rule name:upxHook
Author:@r3dbU7z
Description:Detect artifacts from 'upxHook' - modification of UPX packer
Reference:https://bazaar.abuse.ch/sample/6352be8aa5d8063673aa428c3807228c40505004320232a23d99ebd9ef48478a/

File information


The table below shows additional information about this malware sample such as delivery method and external references.

Web download

Efimer

Executable exe 25f0b776a5fa4bbf0f0727207cdcf58b3f883d2f0e210556350d050b427e69d4

(this sample)

  
Delivery method
Distributed via web download

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