VulnerabilityModified
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.
HIGH 7.0EPSS 0.45%
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.45%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
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 3.0
- 7.0 HIGHCVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 0.45% probability · 38th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-367, CWE-732
- Affected
- valvesoftware/steam client
- Source
- cve@mitre.org
References
- https://amonitoring.ru/article/onemore_steam_eop_0day/Third Party Advisory
- https://habr.com/ru/company/pm/blog/464367/Third Party Advisory
- https://www.youtube.com/watch?v=I93aH86BUaEExploit, Third Party Advisory
- https://www.youtube.com/watch?v=ZCHrjP0cMewExploit, Third Party Advisory
- https://amonitoring.ru/article/onemore_steam_eop_0day/Third Party Advisory
- https://habr.com/ru/company/pm/blog/464367/Third Party Advisory
- https://www.youtube.com/watch?v=I93aH86BUaEExploit, Third Party Advisory
- https://www.youtube.com/watch?v=ZCHrjP0cMewExploit, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.