PT-2019-14045 · Valve · Valve Steam Client

Published 2019-08-21 · Updated 2020-08-24 · CVE-2019-15316

Positive Technologies (AI Summary)

CVSS v3.1

7.0

High

Base vector

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

Name of the Vulnerable Software and Affected Versions Valve Steam Client for Windows versions through 2019-08-20

Description The issue is related to weak folder permissions, which can lead to privilege escalation to NT AUTHORITYSYSTEM. This can be achieved through crafted use of CreateMountPoint.exe and SetOpLock.exe by leveraging a Time-of-Check-to-Time-of-Use (TOCTOU) race condition.

Recommendations For versions through 2019-08-20, update to a version released after 2019-08-20 to resolve the issue.

Exploit

Fix

Incorrect Permission

Time Of Check To Time Of Use

Weakness Enumeration

CWE-732

CWE-367

Related Identifiers

CVE-2019-15316

Affected Products

Valve Steam Client

References · 6

• 🔥 https://youtube.com/watch?v=I93aH86BUaE · Exploit
• 🔥 https://youtube.com/watch?v=ZCHrjP0cMew · Exploit
• https://osv.dev/vulnerability/CVE-2019-15316 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2019-15316 · Security Note
• https://habr.com/ru/company/pm/blog/464367 · Note
• https://amonitoring.ru/article/onemore_steam_eop_0day · Note