CyberSecBulletin
CVE-2024-21338Exploited in the wildNVD status: Analyzed

Microsoft Windows Kernel Exposed IOCTL with Insufficient Access Control

Published Updated By the CyberSecBulletin desk

CVE-2024-21338 is a high-severity untrusted pointer dereference vulnerability in Windows 10 Version 1809 from Microsoft, with a CVSS 3.1 base score of 7.8 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 10.0.17763.5458 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 March 4, 2024, which means attacks have been observed in the wild, including in ransomware campaigns.

Patch now

Attackers are already exploiting this vulnerability, according to CISA.

What to do

  1. Update Windows 10 Version 1809 to 10.0.17763.5458 or a later version.
  2. Update Windows 10 Version 21H2 to 10.0.19044.4046 or a later version.
  3. Update Windows 10 Version 22H2 to 10.0.19045.4046 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, 10.0.17763.5458; 10.0.0 up to, but not including, 10.0.17763.545810.0.17763.5458
MicrosoftWindows 10 Version 21H210.0.19043.0 up to, but not including, 10.0.19044.404610.0.19044.4046
MicrosoftWindows 10 Version 22H210.0.19045.0 up to, but not including, 10.0.19045.404610.0.19045.4046
MicrosoftWindows 11 version 21H210.0.0 up to, but not including, 10.0.22000.277710.0.22000.2777
MicrosoftWindows 11 version 22H210.0.22621.0 up to, but not including, 10.0.22621.315510.0.22621.3155
MicrosoftWindows 11 version 22H310.0.22631.0 up to, but not including, 10.0.22631.315510.0.22631.3155
MicrosoftWindows 11 Version 23H210.0.22631.0 up to, but not including, 10.0.22631.315510.0.22631.3155
MicrosoftWindows Server 201910.0.17763.0 up to, but not including, 10.0.17763.545810.0.17763.5458
MicrosoftWindows Server 2019 (Server Core installation)10.0.17763.0 up to, but not including, 10.0.17763.545810.0.17763.5458
MicrosoftWindows Server 202210.0.20348.0 up to, but not including, 10.0.20348.232210.0.20348.2322
MicrosoftWindows Server 2022, 23H2 Edition (Server Core installation)10.0.25398.0 up to, but not including, 10.0.25398.70910.0.25398.709
MicrosoftWindows 10 1809before 10.0.17763.545810.0.17763.5458
MicrosoftWindows 10 21h2before 10.0.19044.404610.0.19044.4046
MicrosoftWindows 10 22h2before 10.0.19045.404610.0.19045.4046
MicrosoftWindows 11 21h2before 10.0.22000.277710.0.22000.2777
MicrosoftWindows 11 22h2before 10.0.22621.315510.0.22621.3155
MicrosoftWindows 11 23h2before 10.0.22631.315510.0.22631.3155
MicrosoftWindows Server 2022 23h210.0.25398.709 and earlierNot stated

Version data comes from the organisation that assigned the CVE. 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
LowNo special conditions are needed; the attack works reliably.
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:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by CNA (microsoft.com).

Official description

Windows Kernel Elevation of Privilege Vulnerability

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

The underlying weakness: Untrusted Pointer Dereference

The product obtains a value from an untrusted source, converts this value to a pointer, and dereferences the resulting pointer.

More Untrusted Pointer Dereference vulnerabilities (CWE-822)

Timeline

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

References

Third-party and government advisories

Technical write-ups (may include proof of concept)

Recent Untrusted Pointer Dereference vulnerabilities

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