CVE-2020-17055: Windows Remote Access Elevation of Privilege Vulnerability
CVE-2020-17055 is an elevation of privilege vulnerability in Windows Remote Access, rated Important by Microsoft, with a CVSS 3.1 base score of 7.8 (High). An attacker can exploit it by an attacker with local access, with low privileges and without user interaction. Microsoft has not reported exploitation in the wild and rates exploitation as less likely. The EPSS model estimates a 2.85% probability of exploitation activity in the next 30 days, higher than 87% of all scored vulnerabilities. Microsoft released the fix on 10 November 2020 in the November 2020 Patch Tuesday, delivered through 8 security updates (KB4586781, KB4586785, KB4586793, KB4586786 and more). It affects 34 products in 2 product families (Windows, ESU).
Key facts
- CVE ID
- CVE-2020-17055
- Severity
- High CVSS 7.8
- Microsoft severity
- Important
- Impact
- Elevation of Privilege
- Exploited in the wild
- No
- Publicly disclosed
- No
- Exploitation likelihood
- Less Likely
- EPSS
- 2.85% (percentile 87%)
- CISA KEV
- Not listed
- Released
- Last updated
- Patch Tuesday
- November 2020 Patch Tuesday
- Product families
- Windows, ESU
CVSS score and vector
Microsoft scores CVE-2020-17055 at 7.8 (temporal 6.8) using CVSS 3.1. Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
| Metric | Value |
|---|---|
| Attack vector | Local |
| Attack complexity | Low |
| Privileges required | Low |
| User interaction | None |
| Scope | Unchanged |
| Confidentiality impact | High |
| Integrity impact | High |
| Availability impact | High |
| Exploit code maturity | Unproven |
| Remediation level | Official fix |
| Report confidence | Confirmed |
Affected products (34)
Windows
| Product | Security update | Type | Fixed build | Restart |
|---|---|---|---|---|
| Windows 10 Version 20H2 for 32-bit Systems | KB4586781 | Security Update | Yes | |
| Windows Server, version 20H2 (Server Core Installation) | KB4586781 | Security Update | Yes | |
| Windows 10 Version 1803 for 32-bit Systems | KB4586785 | Security Update | Yes | |
| Windows 10 Version 1803 for x64-based Systems | KB4586785 | Security Update | Yes | |
| Windows 10 Version 1803 for ARM64-based Systems | KB4586785 | Security Update | Yes | |
| Windows 10 Version 1809 for 32-bit Systems | KB4586793 | Security Update | Yes | |
| Windows 10 Version 1809 for x64-based Systems | KB4586793 | Security Update | Yes | |
| Windows 10 Version 1809 for ARM64-based Systems | KB4586793 | Security Update | Yes | |
| Windows Server 2019 | KB4586793 | Security Update | Yes | |
| Windows Server 2019 (Server Core installation) | KB4586793 | Security Update | Yes | |
| Windows 10 Version 1909 for 32-bit Systems | KB4586786 | Security Update | Yes | |
| Windows 10 Version 1909 for x64-based Systems | KB4586786 | Security Update | Yes | |
| Windows 10 Version 1909 for ARM64-based Systems | KB4586786 | Security Update | Yes | |
| Windows Server, version 1909 (Server Core installation) | KB4586786 | Security Update | Yes | |
| Windows 10 Version 1903 for 32-bit Systems | KB4586786 | Security Update | Yes | |
| Windows 10 Version 1903 for x64-based Systems | KB4586786 | Security Update | Yes | |
| Windows 10 Version 1903 for ARM64-based Systems | KB4586786 | Security Update | Yes | |
| Windows Server, version 1903 (Server Core installation) | KB4586786 | Security Update | Yes | |
| Windows 10 Version 2004 for 32-bit Systems | KB4586781 | Security Update | Yes | |
| Windows 10 Version 2004 for ARM64-based Systems | KB4586781 | Security Update | Yes | |
| Windows 10 Version 2004 for x64-based Systems | KB4586781 | Security Update | Yes | |
| Windows Server, version 2004 (Server Core installation) | KB4586781 | Security Update | Yes | |
| Windows 10 for 32-bit Systems | KB4586787 | Security Update | Yes | |
| Windows 10 for x64-based Systems | KB4586787 | Security Update | Yes | |
| Windows 10 Version 1607 for 32-bit Systems | KB4586830 | Security Update | Yes | |
| Windows 10 Version 1607 for x64-based Systems | KB4586830 | Security Update | Yes | |
| Windows Server 2016 | KB4586830 | Security Update | Yes | |
| Windows Server 2016 (Server Core installation) | KB4586830 | Security Update | Yes | |
| Windows 8.1 for 32-bit systems | KB4586845 KB4586823 | Monthly Rollup Security Only | Yes Yes | |
| Windows 8.1 for x64-based systems | KB4586845 KB4586823 | Monthly Rollup Security Only | Yes Yes | |
| Windows RT 8.1 | KB4586845 | Monthly Rollup | Yes | |
| Windows 10 Version 20H2 for ARM64-based Systems | KB4586781 | Security Update | Yes |
ESU
Security updates (8)
NIST NVD data
- NVD status
- Modified
- NVD CVSS
- 7.8 (HIGH)
- Published to NVD
- NVD last modified
Affected configurations (CPE)
| Product | Vulnerable versions |
|---|---|
| windows 10 | all listed versions |
| windows 10 20h2 | all listed versions |
| windows 10 1607 | all listed versions |
| windows 10 1709 | all listed versions |
| windows 10 1803 | all listed versions |
| windows 10 1809 | all listed versions |
| windows 10 1903 | all listed versions |
| windows 10 1909 | all listed versions |
| windows 10 2004 | all listed versions |
| windows 8.1 | all listed versions |
| windows rt 8.1 | all listed versions |
| windows server 2008 | all listed versions |
| windows server 2012 r2 | all listed versions |
| windows server 2016 | all listed versions |
| windows server 2016 20h2 | all listed versions |
| windows server 2016 1903 | all listed versions |
| windows server 2016 1909 | all listed versions |
| windows server 2016 2004 | all listed versions |
| windows server 2019 | all listed versions |
References
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-17055 (Patch, Vendor Advisory)
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-17055 (Patch, Vendor Advisory)
Acknowledgments
- Yuki Chen
Revision history
| Version | Date | Description |
|---|---|---|
| 1.0 | Information published. |