CVE-2019-15316: Valve Steam Client for Windows through 2019-08-20 has weak folder permissions, leading to privilege escalation (to NT AUTHORITY\SYSTEM) via crafted use of…

PriorityP429high7CVSS 3.0

AVLACHPRLUINSUCHIHAH

EPSS

0.39%

30.7th percentile

Valve Steam Client for Windows through 2019-08-20 has weak folder permissions, leading to privilege escalation (to NT AUTHORITY\SYSTEM) via crafted use of CreateMountPoint.exe and SetOpLock.exe to leverage a TOCTOU race condition.

Affected

1 ranges

Vendor	Product	Version range	Fixed in
valvesoftware	steam_client	<= 2019-08-20	—

CVSS provenance

nvdv3.07.0HIGHCVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

nvdv2.06.9MEDIUMAV:L/AC:M/Au:N/C:C/I:C/A:C

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