01 Record
CVE-2021-1661
Windows Installer Elevation of Privilege Vulnerability
HighPUBLISHEDCNA: 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:U/RL:O/RC:C
02 Description
Windows Installer Elevation of Privilege Vulnerability
03 Exploitation and scoring
- Exploitation
- Not assessed. CISA has not published an exploitation assessment for this record, and it is not in the KEV catalog. That is an absence of assessment, not a finding of no risk.
- SSVC decision
- Not assessed by CISA
- EPSS probability
- 0.83% probability of exploitation activity in the next 30 days.
- EPSS percentile
- Equal to or higher than the score of 57.3% 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
- Modified. NVD last modified this record on 2026-06-17.
- 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
- 2021-01-12 19:42Z5 YR AGO
- Last updated
- 2024-10-08 16:17Z2 YR AGO
- Reserved
- 2020-12-02
- 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:U/RL:O/RC:C
- Weaknesses
- CWE-665Improper InitializationClass
- Data version
- 5.1
- Document digest
- 38a38b0c2dd681adf26f70bdcf3d28abfbe8408bd0e819ae706cf18f16e88c6b
05 Affected products
VendorProductVersionsPlatforms
MicrosoftWindows 10 Version 180310.0.0 to < publication32-bit Systems, x64-based Systems, ARM64-based Systems
MicrosoftWindows 10 Version 180910.0.0 to < publication32-bit Systems, x64-based Systems, ARM64-based Systems
MicrosoftWindows 10 Version 190910.0.0 to < publication32-bit Systems, x64-based Systems, ARM64-based Systems
MicrosoftWindows Server, version 1909 (Server Core installation)10.0.0 to < publicationx64-based Systems
MicrosoftWindows 10 Version 200410.0.0 to < publication32-bit Systems, ARM64-based Systems, x64-based Systems
MicrosoftWindows Server 2008 Service Pack 2 (Server Core installation)6.0.0 to < publication32-bit Systems, x64-based Systems
MicrosoftWindows Server 2008 R2 Service Pack 1 (Server Core installation)6.0.0 to < publicationx64-based Systems
06 References
- msrc.microsoft.comWindows Installer Elevation of Privilege Vulnerabilityhttps://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-1661
- portal.msrc.microsoft.comhttps://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-1661