CyberSecBulletin
CVE-2022-26923Exploited in the wildNVD status: Analyzed

Microsoft Active Directory Domain Services Privilege Escalation

Published Updated By the CyberSecBulletin desk

CVE-2022-26923 is a high-severity improper certificate validation vulnerability in Windows 10 Version 1809 from Microsoft, with a CVSS 2.0 base score of 9.0 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. The record lists version 10.0.17763.4252 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 August 18, 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 10.0.17763.4252 or a later version.
  2. Update Windows Server 2019 to 10.0.17763.4252 or a later version.
  3. Update Windows Server 2019 (Server Core installation) to 10.0.17763.4252 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, 10.0.17763.4252; 10.0.0 up to, but not including, 10.0.17763.425210.0.17763.4252
MicrosoftWindows Server 201910.0.17763.0 up to, but not including, 10.0.17763.425210.0.17763.4252
MicrosoftWindows Server 2019 (Server Core installation)10.0.17763.0 up to, but not including, 10.0.17763.425210.0.17763.4252
MicrosoftWindows 10 Version 190910.0.0 up to, but not including, 10.0.18363.227410.0.18363.2274
MicrosoftWindows 10 Version 21H110.0.0 up to, but not including, 10.0.19043.170610.0.19043.1706
MicrosoftWindows Server 202210.0.20348.0 up to, but not including, 10.0.20348.166810.0.20348.1668
MicrosoftWindows 10 Version 20H210.0.0 up to, but not including, 10.0.19042.170610.0.19042.1706
MicrosoftWindows Server version 20H210.0.0 up to, but not including, 10.0.19042.170610.0.19042.1706
MicrosoftWindows 11 version 21H210.0.0 up to, but not including, 10.0.22000.181710.0.22000.1817
MicrosoftWindows 10 Version 21H210.0.19043.0 up to, but not including, 10.0.19043.170610.0.19043.1706
MicrosoftWindows 10 Version 150710.0.10240.0 up to, but not including, 10.0.10240.1929710.0.10240.19297
MicrosoftWindows 10 Version 160710.0.14393.0 up to, but not including, 10.0.14393.585010.0.14393.5850
MicrosoftWindows Server 201610.0.14393.0 up to, but not including, 10.0.14393.585010.0.14393.5850
MicrosoftWindows Server 2016 (Server Core installation)10.0.14393.0 up to, but not including, 10.0.14393.585010.0.14393.5850
MicrosoftWindows 8.16.3.0 up to, but not including, 6.3.9600.203716.3.9600.20371
MicrosoftWindows Server 2012 R26.3.9600.0 up to, but not including, 6.3.9600.209196.3.9600.20919
MicrosoftWindows Server 2012 R2 (Server Core installation)6.3.9600.0 up to, but not including, 6.3.9600.209196.3.9600.20919
MicrosoftWindows 10 1507before 10.0.10240.1929710.0.10240.19297
MicrosoftWindows 10 1607before 10.0.14393.585010.0.14393.5850
MicrosoftWindows 10 1809before 10.0.17763.425210.0.17763.4252
MicrosoftWindows 10 1909before 10.0.18363.227410.0.18363.2274
MicrosoftWindows 10 20h2before 10.0.19042.170610.0.19042.1706
MicrosoftWindows 10 21h1before 10.0.19043.170610.0.19043.1706
MicrosoftWindows 10 21h2before 10.0.19044.170610.0.19044.1706
MicrosoftWindows 11 21h2before 10.0.22000.181710.0.22000.1817

Version data comes from the organisation that assigned the CVE; 2 further products are omitted here. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Access vector
NetworkCan be exploited remotely over a network.
Access complexity
LowNo special conditions are needed.
Authentication
SingleOne 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:N/AC:L/Au:S/C:C/I:C/A:C. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.18.8HighCNA (microsoft.com)
CVSS 2.09.0HighNVD

Official description

Active Directory Domain Services Elevation of Privilege Vulnerability

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

The underlying weakness: Improper Certificate Validation

The product does not validate, or incorrectly validates, a certificate.

How developers prevent this class of flaw

  • Certificates should be carefully managed and checked to assure that data are encrypted with the intended owner's public key.
  • If certificate pinning is being used, ensure that all relevant properties of the certificate are fully validated before the certificate is pinned, including the hostname.

More Improper Certificate Validation vulnerabilities (CWE-295)

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 Certificate Validation vulnerabilities

Spotted an error? Tell us.