Security News > 2021 > July > Microsoft shares workarounds for new Windows 10 zero-day bug
Microsoft has shared a workaround for a Windows 10 zero-day vulnerability that can let attackers gain admin rights on vulnerable systems and execute arbitrary code with SYSTEM privileges.
"An elevation of privilege vulnerability exists because of overly permissive Access Control Lists on multiple system files, including the Security Accounts Manager database," Microsoft explains in a security advisory published on Tuesday evening.
As Microsoft further revealed, this zero-day vulnerability impacts all Windows client and server versions released during the last three years, since October 2018, starting with Windows 10 1809 and Windows Server 2019.
Microsoft recommends restricting access to the problematic folder AND deleting Volume Shadow Copy Service shadow copies to mitigate this issue.
Microsoft is still investigating the vulnerability and is working on a patch that will most likely be released as an out-of-band security update later this week.
Update: Added more info on affected Windows versions, deleting shadow copies.
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