[+] Credits: John Page (aka hyp3rlinx)   
[+] Website:  
[+] Source:  
[+] ISR: ApparitionSec   
Windows Defender  
[Vulnerability Type]  
Windows Defender Detection Mitigation Bypass  
[CVE Reference]  
[Security Issue]  
Typically, Windows Defender detects and prevents TrojanWin32Powessere.G aka "POWERLIKS" type execution that leverages rundll32.exe. Attempts at execution fail  
and attackers will typically get an "Access is denied" error message.  
Back in 2022, I first disclosed how that could be easily bypassed by passing an extra path traversal when referencing mshtml but since has been mitigated.  
Recently Feb 7, 2024, I disclosed using multi-commas "," will bypass that mitigation but has since been fixed again.  
The fix was short lived as I find yet another third trivial bypass soon after.  
Open command prompt as Administrator.  
C:\sec>rundll32.exe javascript:"\..\..\mshtml,,RunHTMLApplication ";alert(13)  
Access is denied.  
C:\sec>rundll32.exe javascript:"\\..\\..\\mshtml\\..\\..\\mshtml,RunHTMLApplication ";alert('HYP3RLINX')  
[Video PoC URL]  
[Network Access]  
[Disclosure Timeline]  
Vendor Notification:   
February 16, 2024 : Public Disclosure  
[+] 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. All content (c).