CyberSecBulletin
CVE-2022-21919Exploited in the wildNVD status: Analyzed

Microsoft Windows User Profile Service Privilege Escalation

Published Updated By the CyberSecBulletin desk

CVE-2022-21919 is a medium-severity improper link resolution before file access vulnerability in Windows 10 Version 1809 from Microsoft, with a CVSS 2.0 base score of 6.9 out of 10. It can be exploited with local access to the system by an unauthenticated attacker, without any action from a user. The record lists version 10.0.17763.2452 as the first without the flaw, so updating Windows 10 Version 1809 to that release or later removes the exposure. CISA added it to the Known Exploited Vulnerabilities catalogue on April 25, 2022, which means attacks have been observed in the wild.

Patch now

Attackers are already exploiting this vulnerability, according to CISA.

What to do

  1. Update Windows 10 Version 1809 to 10.0.17763.2452 or a later version.
  2. Update Windows Server 2019 to 10.0.17763.2452 or a later version.
  3. Update Windows Server 2019 (Server Core installation) to 10.0.17763.2452 or a later version.
  4. CISA's required action: Apply updates per vendor instructions.
  5. Read the advisory on msrc.microsoft.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
MicrosoftWindows 10 Version 180910.0.17763.0 up to, but not including, 10.0.17763.2452; 10.0.0 up to, but not including, 10.0.17763.245210.0.17763.2452
MicrosoftWindows Server 201910.0.17763.0 up to, but not including, 10.0.17763.245210.0.17763.2452
MicrosoftWindows Server 2019 (Server Core installation)10.0.17763.0 up to, but not including, 10.0.17763.245210.0.17763.2452
MicrosoftWindows 10 Version 190910.0.0 up to, but not including, 10.0.18363.203710.0.18363.2037
MicrosoftWindows 10 Version 21H110.0.0 up to, but not including, 10.0.19043.146610.0.19043.1466
MicrosoftWindows Server 202210.0.20348.0 up to, but not including, 10.0.20348.46910.0.20348.469
MicrosoftWindows 10 Version 20H210.0.0 up to, but not including, 10.0.19042.146610.0.19042.1466
MicrosoftWindows Server version 20H210.0.0 up to, but not including, 10.0.19042.146610.0.19042.1466
MicrosoftWindows 11 version 21H210.0.0 up to, but not including, 10.0.22000.43410.0.22000.434
MicrosoftWindows 10 Version 21H210.0.19043.0 up to, but not including, 10.0.19043.146610.0.19043.1466
MicrosoftWindows 10 Version 150710.0.10240.0 up to, but not including, 10.0.10240.1917710.0.10240.19177
MicrosoftWindows 10 Version 160710.0.14393.0 up to, but not including, 10.0.14393.488610.0.14393.4886
MicrosoftWindows Server 201610.0.14393.0 up to, but not including, 10.0.14393.488610.0.14393.4886
MicrosoftWindows Server 2016 (Server Core installation)10.0.14393.0 up to, but not including, 10.0.14393.488610.0.14393.4886
MicrosoftWindows 76.1.0 up to, but not including, 6.1.7601.258296.1.7601.25829
MicrosoftWindows 7 Service Pack 16.1.0 up to, but not including, 6.1.7601.258296.1.7601.25829
MicrosoftWindows 8.16.3.0 up to, but not including, 6.3.9600.202466.3.9600.20246
MicrosoftWindows Server 2008 Service Pack 26.0.6003.0 up to, but not including, 6.0.6003.213496.0.6003.21349
MicrosoftWindows Server 2008 Service Pack 2 (Server Core installation)6.0.6003.0 up to, but not including, 6.0.6003.213496.0.6003.21349
MicrosoftWindows Server 2008 R2 Service Pack 16.1.7601.0 up to, but not including, 6.1.7601.258296.1.7601.25829
MicrosoftWindows Server 2008 R2 Service Pack 1 (Server Core installation)6.1.7601.0 up to, but not including, 6.1.7601.258296.1.7601.25829
MicrosoftWindows Server 20126.2.9200.0 up to, but not including, 6.2.9200.235846.2.9200.23584
MicrosoftWindows Server 2012 (Server Core installation)6.2.9200.0 up to, but not including, 6.2.9200.235846.2.9200.23584
MicrosoftWindows Server 2012 R26.3.9600.0 up to, but not including, 6.3.9600.202466.3.9600.20246
MicrosoftWindows Server 2012 R2 (Server Core installation)6.3.9600.0 up to, but not including, 6.3.9600.202466.3.9600.20246

Version data comes from the organisation that assigned the CVE; 11 further products are omitted here. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Access vector
LocalLocal access is required.
Access complexity
MediumSome conditions must be met.
Authentication
NoneNo login is needed.
Confidentiality
CompleteAll data can be read.
Integrity
CompleteAny data can be modified.
Availability
CompleteThe system can be shut down completely.

Vector: AV:L/AC:M/Au:N/C:C/I:C/A:C. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.17.0HighCNA (microsoft.com)
CVSS 2.06.9MediumNVD

Official description

Windows User Profile Service Elevation of Privilege Vulnerability

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Improper Link Resolution Before File Access

The product attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource.

How developers prevent this class of flaw

  • Follow the principle of least privilege when assigning access rights to entities in a software system. Denying access to a file can prevent an attacker from replacing that file with a link to a sensitive file. Ensure good compartmentalization in the system to provide protected areas that can be trusted.

More Improper Link Resolution Before File Access vulnerabilities (CWE-59)

Timeline

  1. CVE record published.
  2. Added to CISA's Known Exploited Vulnerabilities catalogue.
  3. Deadline for US federal agencies to remediate, set by CISA.
  4. CISA published its SSVC assessment (exploitation: active, automatable: no, technical impact: total).
  5. Record last changed materially (score, affected products, status or references).

References

Third-party and government advisories

Recent Improper Link Resolution Before File Access vulnerabilities

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