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 CreateMountPoint.exe and SetOpLock.exe to leverage a TOCTOU race condition.

CVSS v3.0 7.0 HIGH
CVSS v2.0 6.9 MEDIUM

7.0^/10

CVSS v3.0 : HIGH

V3 Legend

Vector : AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

Exploitability : 1.0 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

6.9^/10

CVSS v2.0 : MEDIUM

V2 Legend

Vector : AV:L/AC:M/Au:N/C:C/I:C/A:C

Exploitability : 3.4 / Impact : 10.0

Access Vector LOCAL

Access Complexity MEDIUM

Authentication NONE

Confidentiality Impact COMPLETE

Integrity Impact COMPLETE

Availability Impact COMPLETE

References

Link	Resource
https://habr.com/ru/company/pm/blog/464367/	Third Party Advisory
https://www.youtube.com/watch?v=ZCHrjP0cMew	Exploit Third Party Advisory
https://amonitoring.ru/article/onemore_steam_eop_0day/	Third Party Advisory
https://www.youtube.com/watch?v=I93aH86BUaE	Exploit Third Party Advisory

Configurations

Configuration 1 (hide)

AND

cpe:2.3:a:valvesoftware:steam_client:*:*:*:*:*:*:*:*

cpe:2.3:o:microsoft:windows:-:*:*:*:*:*:*:*

Information

Published : 2019-08-21 13:15

Updated : 2020-08-24 10:37

NVD link : CVE-2019-15316

Mitre link : CVE-2019-15316

JSON object : View

CWE

CWE-732

Incorrect Permission Assignment for Critical Resource

CWE-367

Time-of-check Time-of-use (TOCTOU) Race Condition

Products Affected

valvesoftware

steam_client

microsoft

windows

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7.0 /10