CyberSecBulletin
CVE-2019-0803Exploited in the wildNVD status: Analyzed

Microsoft Win32k Privilege Escalation

Published Updated By the CyberSecBulletin desk

CVE-2019-0803 is a high-severity vulnerability in Windows 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. Affected Windows versions: 7 for 32-bit Systems Service Pack 1; 7 for x64-based Systems Service Pack 1; 8.1 for 32-bit systems, and others listed below. The record does not name a fixed version, so check the vendor advisory. CISA added it to the Known Exploited Vulnerabilities catalogue on November 3, 2021, 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. Check which version of Windows you run against the affected versions below, and install the vendor's latest release.
  2. CISA's required action: Apply updates per vendor instructions.
  3. Read the advisory on portal.msrc.microsoft.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
MicrosoftWindows7 for 32-bit Systems Service Pack 1; 7 for x64-based Systems Service Pack 1; 8.1 for 32-bit systems; 8.1 for x64-based systems; RT 8.1; 10 for 32-bit Systems; 10 for x64-based Systems; 10 Version 1607 for 32-bit Systems; and 12 more rangesNot stated
MicrosoftWindows Server2008 R2 for Itanium-Based Systems Service Pack 1; 2008 R2 for x64-based Systems Service Pack 1; 2008 for 32-bit Systems Service Pack 2 (Core installation); 2012; 2012 (Core installation); 2012 R2; 2012 R2 (Core installation); 2016; and 8 more rangesNot stated
MicrosoftWindows 10 1507Not specified in the recordNot stated
MicrosoftWindows 10 1607Not specified in the recordNot stated
MicrosoftWindows 10 1703Not specified in the recordNot stated
MicrosoftWindows 10 1709Not specified in the recordNot stated
MicrosoftWindows 10 1803Not specified in the recordNot stated
MicrosoftWindows 10 1809Not specified in the recordNot stated
MicrosoftWindows 7Not specified in the recordNot stated
MicrosoftWindows 8.1Not specified in the recordNot stated
MicrosoftWindows Rt 8.1Not specified in the recordNot stated
MicrosoftWindows Server 1709Not specified in the recordNot stated
MicrosoftWindows Server 1803Not specified in the recordNot stated
MicrosoftWindows Server 2008r2Not stated
MicrosoftWindows Server 2012r2Not stated
MicrosoftWindows Server 2016Not specified in the recordNot stated
MicrosoftWindows Server 2019Not specified in the recordNot 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 NVD.

Scoring systemScoreSeverityScored by
CVSS 3.17.8HighNVD
CVSS 3.17.8HighCISA (ADP)
CVSS 2.07.2HighNVD

Official description

An elevation of privilege vulnerability exists in Windows when the Win32k component fails to properly handle objects in memory, aka 'Win32k Elevation of Privilege Vulnerability'. This CVE ID is unique from CVE-2019-0685, CVE-2019-0859.

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

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

Other vulnerabilities in Windows

All Windows vulnerabilities

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