CVE-2020-15530 json
An issue was discovered in Valve Steam Client 2.10.91.91.
published 2020-07-05 6 y ago modified 2026-06-17 4 mo ago also EUVD-2020-7517
- cvss
- 7.8
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.5%
- EPSS 0.5% chance of exploitation in 30 days, percentile 45%
- public exploits
- 0
- none known
Summary
An issue was discovered in Valve Steam Client 2.10.91.91. The installer allows local users to gain NT AUTHORITY\SYSTEM privileges because some parts of %PROGRAMFILES(X86)%\Steam and/or %COMMONPROGRAMFILES(X86)%\Steam have weak permissions during a critical time window. An attacker can make this time window arbitrarily long by using opportunistic locks.
Exploit prediction
0.55% chance of exploitation in the next 30 days, higher than 45% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- daniels-it-blog.blogspot.com http://daniels-it-blog.blogspot.com/2020/07/steam-arbitrary-code-execution-part-2.html referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| NVD | 2.0 | 7.2 | AV:L/AC:L/Au:N/C:C/I:C/A:C |
Classification
- Weakness
-
- CWE-362 Concurrent Execution using Shared Resource with Improper Synchronization
References
-
daniels-it-blog.blogspot.com
/2020/07/steam-arbitrary-code-execution-part-2.html
exploit, third-party-advisory
Sources
- CVE List CVE-2020-15530
- NVD CVE-2020-15530
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