How to Mitigate Microsoft Windows 10, 11 SeriousSAM Vulnerability
Jul 26, 2021
Microsoft Windows 10 and Windows 11 users are at risk of a new unpatched vulnerability that was recently disclosed publicly. As we reported last week, the vulnerability — SeriousSAM — allows attackers with low-level permissions to access Windows system files to perform a Pass-the-Hash (and potentially Silver Ticket) attack. Attackers can exploit this vulnerability to obtain hashed passwords stored in the Security Account Manager (SAM) and Registry, and ultimately run arbitrary code with SYSTEM privileges. SeriousSAM vulnerability, tracked as CVE-2021-36934 , exists in the default configuration of Windows 10 and Windows 11, specifically due to a setting that allows 'read' permissions to the built-in user's group that contains all local users. As a result, built-in local users have access to read the SAM files and the Registry, where they can also view the hashes. Once the attacker has 'User' access, they can use a tool such as Mimikatz to gain access to the Re...
