Discovery / credits: Malvuln (John Page aka hyp3rlinx) (c) 2022
Original source: https://malvuln.com/advisory/13e878ed7e547523cffc5728f6ba4190.txt
Contact: malvuln13@gmail.com
Media: twitter.com/malvuln

Threat: Yashma Ransomware Builder v1.2
Vulnerability: Insecure Permissions
Description: The malware creates PE files with insecure permissions when writing to c:\ drive, granting change (C) permissions to the authenticated user group. Standard users can rename the executable dropped by the malware to disable it or replace it with their own executable. Then wait for a privileged user to logon to the infected machine to potentially escalate privileges.
Family: Yashma
Type: PE32
MD5: 13e878ed7e547523cffc5728f6ba4190
Vuln ID: MVID-2022-0613 
Disclosure: 06/23/2022


Exploit/PoC:
C:\>cacls hate.exe
C:\hate.exe BUILTIN\Administrators:(ID)F
            NT AUTHORITY\SYSTEM:(ID)F
            BUILTIN\Users:(ID)R
            NT AUTHORITY\Authenticated Users:(ID)C


C:\>dir hate.exe
 Volume in drive C has no label.

 Directory of C:\

05/14/2022  01:20 AM            54,784 hate.exe
               1 File(s)         54,784 bytes


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