// For flags

CVE-2020-0840

Microsoft Windows AppX Deployment Service Hard Link Escalation of Privilege Vulnerability

Severity Score

7.8
*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

-
*SSVC
Descriptions

An elevation of privilege vulnerability exists when Windows improperly handles hard links, aka 'Windows Hard Link Elevation of Privilege Vulnerability'. This CVE ID is unique from CVE-2020-0841, CVE-2020-0849, CVE-2020-0896.

Existe una vulnerabilidad de elevación de privilegios cuando Windows maneja inapropiadamente los enlaces físicos, también se conoce como "Windows Hard Link Elevation of Privilege Vulnerability"'. Este ID de CVE es diferente de CVE-2020-0841, CVE-2020-0849, CVE-2020-0896.

This vulnerability allows local attackers to escalate privileges on affected installations of Microsoft Windows. An attacker must first obtain the ability to execute low-privileged code on the target system in order to exploit this vulnerability.
The specific flaw exists within the AppX Deployment Service. By creating a hard link, an attacker can abuse the service to overwrite the contents of a chosen file. An attacker can leverage this vulnerability to escalate privileges and execute code in the context of SYSTEM.

*Credits: JeongOh Kyea(@kkokkokye) of THEORI
CVSS Scores
Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High
Attack Vector
Local
Attack Complexity
Low
Authentication
None
Confidentiality
Complete
Integrity
Complete
Availability
Complete
* Common Vulnerability Scoring System
SSVC
  • Decision:-
Exploitation
-
Automatable
-
Tech. Impact
-
* Organization's Worst-case Scenario
Timeline
  • 2019-11-04 CVE Reserved
  • 2020-03-12 CVE Published
  • 2024-08-04 CVE Updated
  • 2024-09-08 EPSS Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
CAPEC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Microsoft
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Windows 10
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--
Affected
Microsoft
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Windows 10
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1607
Search vendor "Microsoft" for product "Windows 10" and version "1607"
-
Affected
Microsoft
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Windows 10
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1709
Search vendor "Microsoft" for product "Windows 10" and version "1709"
-
Affected
Microsoft
Search vendor "Microsoft"
Windows 10
Search vendor "Microsoft" for product "Windows 10"
1803
Search vendor "Microsoft" for product "Windows 10" and version "1803"
-
Affected
Microsoft
Search vendor "Microsoft"
Windows 10
Search vendor "Microsoft" for product "Windows 10"
1809
Search vendor "Microsoft" for product "Windows 10" and version "1809"
-
Affected
Microsoft
Search vendor "Microsoft"
Windows 10
Search vendor "Microsoft" for product "Windows 10"
1903
Search vendor "Microsoft" for product "Windows 10" and version "1903"
-
Affected
Microsoft
Search vendor "Microsoft"
Windows 10
Search vendor "Microsoft" for product "Windows 10"
1909
Search vendor "Microsoft" for product "Windows 10" and version "1909"
-
Affected
Microsoft
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Windows 8.1
Search vendor "Microsoft" for product "Windows 8.1"
--
Affected
Microsoft
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Windows Rt 8.1
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--
Affected
Microsoft
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Windows Server 2012
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r2
Search vendor "Microsoft" for product "Windows Server 2012" and version "r2"
-
Affected
Microsoft
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Windows Server 2016
Search vendor "Microsoft" for product "Windows Server 2016"
--
Affected
Microsoft
Search vendor "Microsoft"
Windows Server 2016
Search vendor "Microsoft" for product "Windows Server 2016"
1803
Search vendor "Microsoft" for product "Windows Server 2016" and version "1803"
-
Affected
Microsoft
Search vendor "Microsoft"
Windows Server 2016
Search vendor "Microsoft" for product "Windows Server 2016"
1903
Search vendor "Microsoft" for product "Windows Server 2016" and version "1903"
-
Affected
Microsoft
Search vendor "Microsoft"
Windows Server 2016
Search vendor "Microsoft" for product "Windows Server 2016"
1909
Search vendor "Microsoft" for product "Windows Server 2016" and version "1909"
-
Affected
Microsoft
Search vendor "Microsoft"
Windows Server 2019
Search vendor "Microsoft" for product "Windows Server 2019"
--
Affected