01 Record
CVE-2021-33771
Windows Kernel Elevation of Privilege Vulnerability
HighKEVPUBLISHEDCNA: microsoft
CNA base score7.8 CVSS v3.xCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:F/RL:O/RC:C
02 Description
Windows Kernel Elevation of Privilege Vulnerability
03 Exploitation and scoring
- Exploitation
- Exploited in the wild. Listed in the CISA Known Exploited Vulnerabilities catalog on 2021-11-03. Federal remediation due 2021-11-17.
- SSVC decision
- ExploitationactiveCISA reports credible evidence of active exploitation.
- AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
- Technical ImpacttotalSuccessful exploitation gives total control of the vulnerable component.
- EPSS probability
- 10.17% probability of exploitation activity in the next 30 days.
- EPSS percentile
- Equal to or higher than the score of 95.2% of scored records. A rank, not a probability.
- NVD base score
- 7.8 (CVSS v3.x), scored by the NVD independently of the CNA.
- NVD CVSS vector
- CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- NVD analysis status
- Analyzed. NVD last modified this record on 2026-08-10.
- Red Hat severity
- No Red Hat rating. Red Hat rates the CVEs that affect its products.
Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.
04 Metadata
- Published
- 2021-07-14 17:53Z5 YR AGO
- Last updated
- 2026-08-10 15:11Z2 MO AGO
- Reserved
- 2021-05-28
- Assigning CNA
- microsoft
- Record state
- PUBLISHED
- Severity
- High (CVSS 7.8)
- CNA CVSS vector
- CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:F/RL:O/RC:C
- Weaknesses
- No CWE assigned
- Data version
- 5.2
- Document digest
- ab5f33303d8cd4997cd7df5755839cee7022e876a6712472fc32d52812e45a5b
05 Affected products
VendorProductVersionsPlatforms
MicrosoftWindows 10 Version 180910.0.17763.0 to < 10.0.17763.2061, 10.0.0 to < 10.0.17763.206132-bit Systems, x64-based Systems, ARM64-based Systems
MicrosoftWindows 10 Version 190910.0.0 to < 10.0.18363.167932-bit Systems, ARM64-based Systems, x64-based Systems
MicrosoftWindows 10 Version 200410.0.0 to < 10.0.19041.111032-bit Systems, ARM64-based Systems, x64-based Systems
MicrosoftWindows 10 Version 21H110.0.0 to < 10.0.19043.111032-bit Systems, ARM64-based Systems, x64-based Systems
MicrosoftWindows Server 2012 R2 (Server Core installation)6.3.9600.0 to < 6.3.9600.20069x64-based Systems
MicrosoftWindows Server 2016 (Server Core installation)10.0.14393.0 to < 10.0.14393.4530x64-based Systems
MicrosoftWindows Server 2019 (Server Core installation)10.0.17763.0 to < 10.0.17763.2061x64-based Systems
06 References
- msrc.microsoft.comWindows Kernel Elevation of Privilege Vulnerabilityhttps://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-33771
- portal.msrc.microsoft.comhttps://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-33771
- www.cisa.govhttps://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-33771