lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [day] [month] [year] [list]
Date: Fri, 19 Mar 2021 21:47:34 -0400
From: malvuln <malvuln13@...il.com>
To: fulldisclosure@...lists.org
Subject: [FD] HEUR.Trojan.Win32.Generic / Insecure Permissions

Discovery / credits: Malvuln - malvuln.com (c) 2021
Original source:
https://malvuln.com/advisory/c60f00700bd73ca369195bd32a3f16a3.txt
Contact: malvuln13@...il.com
Media: twitter.com/malvuln

Threat: HEUR.Trojan.Win32.Generic
Vulnerability: Insecure Permissions
Description: The specimen creates a dir named "RECYCLER" under c:\ drive
and grants change (C) permissions to the authenticated user group. Within
the RECYCLER dir exists an hidden dir named with security identifier (SID),
which in turn contains a dropped executable named "i7764tg.exe". 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.
Type: PE32
MD5: c60f00700bd73ca369195bd32a3f16a3
Vuln ID: MVID-2021-0136
Dropped files: i7764tg.exe
Disclosure: 03/19/2021


Exploit/PoC:
C:\>cacls \RECYCLER
C:\RECYCLER BUILTIN\Administrators:(OI)(CI)(ID)F
            NT AUTHORITY\SYSTEM:(OI)(CI)(ID)F
            BUILTIN\Users:(OI)(CI)(ID)R
            NT AUTHORITY\Authenticated Users:(ID)C
            NT AUTHORITY\Authenticated Users:(OI)(CI)(IO)(ID)C


C:\RECYCLER>dir /a
 Volume in drive C has no label.

 Directory of C:\RECYCLER

03/02/2021  11:06 AM    &lt;DIR&gt;
S-1-5-21-0243556031-888888379-781863308-9761
               0 File(s)              0 bytes

C:\RECYCLER>cd S-1-5-21-0243556031-888888379-781863308-9761

C:\RECYCLER\S-1-5-21-0243556031-888888379-781863308-9761>dir /a
 Volume in drive C has no label.

 Directory of C:\RECYCLER\S-1-5-21-0243556031-888888379-781863308-9761

03/02/2021  11:06 AM                63 Desktop.ini
06/17/2012  02:29 AM            45,056 i7764tg.exe


Disclaimer: The information contained within this advisory is supplied
"as-is" with no warranties or guarantees of fitness of use or otherwise.
Permission is hereby granted for the redistribution of this advisory,
provided that it is not altered except by reformatting it, and that due
credit is given. Permission is explicitly given for insertion in
vulnerability databases and similar, provided that due credit is given to
the author. The author is not responsible for any misuse of the information
contained herein and accepts no responsibility for any damage caused by the
use or misuse of this information. The author prohibits any malicious use
of security related information or exploits by the author or elsewhere. Do
not attempt to download Malware samples. The author of this website takes
no responsibility for any kind of damages occurring from improper Malware
handling or the downloading of ANY Malware mentioned on this website or
elsewhere. All content Copyright (c) Malvuln.com (TM).

_______________________________________________
Sent through the Full Disclosure mailing list
https://nmap.org/mailman/listinfo/fulldisclosure
Web Archives & RSS: http://seclists.org/fulldisclosure/

Powered by blists - more mailing lists