CyberSecBulletin
CVE-2023-28229Exploited in the wildNVD status: Analyzed

Microsoft Windows CNG Key Isolation Service Privilege Escalation

CVE-2023-28229 is a high-severity sensitive data storage in improperly locked memory vulnerability in Windows 10 Version 1809 from Microsoft, with a CVSS 3.1 base score of 7.0 out of 10. It can be exploited with local access to the system 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 October 4, 2023, 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 mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
  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 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, 10.0.19042.284610.0.19042.2846
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, 10.0.19044.284610.0.19044.2846
MicrosoftWindows 11 version 22H210.0.22621.0 up to, but not including, 10.0.22621.155510.0.22621.1555
MicrosoftWindows 10 Version 22H210.0.19045.0 up to, but not including, 10.0.19045.284610.0.19045.2846
MicrosoftWindows 10 Version 150710.0.10240.0 up to, but not including, 10.0.10240.1986910.0.10240.19869
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 Server 2008 Service Pack 26.0.6003.0 up to, but not including, 6.0.6003.220156.0.6003.22015
MicrosoftWindows Server 2008 Service Pack 2 (Server Core installation)6.0.6003.0 up to, but not including, 6.0.6003.220156.0.6003.22015
MicrosoftWindows Server 2008 R2 Service Pack 16.1.7601.0 up to, but not including, 6.1.7601.264666.1.7601.26466
MicrosoftWindows Server 2008 R2 Service Pack 1 (Server Core installation)6.1.7601.0 up to, but not including, 6.1.7601.264666.1.7601.26466
MicrosoftWindows Server 20126.2.9200.0 up to, but not including, 6.2.9200.242166.2.9200.24216
MicrosoftWindows Server 2012 (Server Core installation)6.2.9200.0 up to, but not including, 6.2.9200.242166.2.9200.24216
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 10.0.10240.1986910.0.10240.19869
MicrosoftWindows 10 1607before 10.0.14393.585010.0.14393.5850
MicrosoftWindows 10 1809before 10.0.17763.425210.0.17763.4252
MicrosoftWindows 10 20h2before 10.0.19042.284610.0.19042.2846

Version data comes from the organisation that assigned the CVE; 5 further products are omitted here. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
LocalThe attacker needs local access or must trick a user into running something.
Attack complexity
HighSuccess depends on conditions outside the attacker's control.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by CNA (microsoft.com).

Official description

Windows CNG Key Isolation Service Elevation of Privilege Vulnerability

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

The underlying weakness: Sensitive Data Storage in Improperly Locked Memory

The product stores sensitive data in memory that is not locked, or that has been incorrectly locked.

How developers prevent this class of flaw

  • Identify data that needs to be protected from swapping and choose platform-appropriate protection mechanisms.
  • When using potentially risky functions such as mlock() or VirtualLock(), check return values to ensure that locking operations are successful.

More Sensitive Data Storage in Improperly Locked Memory vulnerabilities (CWE-591)

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

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