Vulnerable component: Windows
CVSSv3 score: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:H/RL:O/RC:C
CWE-ID: CWE-264 - Permissions, Privileges, and Access Controls
The vulnerability allows a local attacker to gain elevated privileges on the target system.
The vulnerability exists due to ALPC access control flaw. A local attacker can create a hard link from a readable file on the system to a '.job' file in the 'c:\windows\tasks' directory, invoke the _SchRpcSetSecurity() method of the task scheduler service ALPC endpoint to overwrite the linked file and gain system level privileges on the target system. The vulnerability was dubbed "SendboxEscaper".
Note: the vulnerability is being exploited in the wild by the PowerPool group.