MEDIUM
Windows Installer Spoofing Vulnerability
Published Jul 14, 2021
6.2
MEDIUMCVSS 3.1
EPSS 0.72%
Description
Windows Installer Spoofing Vulnerability
Affected products
-
- Version 10.0.10240.0StatusaffectedConstraints<10.0.10240.19003
- Version
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- Version 10.0.14393.0StatusaffectedConstraints<10.0.14393.4530
- Version
-
- Version 10.0.0StatusaffectedConstraints<10.0.17763.2061
- Version 10.0.17763.0StatusaffectedConstraints<10.0.17763.2061
- Version
-
- Version 10.0.0StatusaffectedConstraints<10.0.18363.1679
- Version
-
- Version 10.0.0StatusaffectedConstraints<10.0.19041.1110
- Version
-
- Version 10.0.0StatusaffectedConstraints<10.0.19042.1110
- Version
-
- Version 10.0.0StatusaffectedConstraints<10.0.19043.1110
- Version
-
- Version 6.1.0StatusaffectedConstraints<6.1.7601.25661
- Version
-
- Version 6.1.0StatusaffectedConstraints<6.1.7601.25661
- Version
-
- Version 6.3.0StatusaffectedConstraints<6.3.9600.20069
- Version
-
- Version 6.1.7601.0StatusaffectedConstraints<6.1.7601.25661
- Version
- Vendor Microsoft Product Windows Server 2008 R2 Service Pack 1 (Server Core installation) Defaultn/a
- Version 6.1.7601.0StatusaffectedConstraints<6.1.7601.25661
- Version
-
- Version 6.0.6003.0StatusaffectedConstraints<6.0.6003.21167
- Version
-
- Version 6.0.6003.0StatusaffectedConstraints<6.0.6003.21167
- Version
-
- Version 6.2.9200.0StatusaffectedConstraints<6.2.9200.23409
- Version
-
- Version 6.2.9200.0StatusaffectedConstraints<6.2.9200.23409
- Version
-
- Version 6.3.9600.0StatusaffectedConstraints<6.3.9600.20069
- Version
-
- Version 6.3.9600.0StatusaffectedConstraints<6.3.9600.20069
- Version
-
- Version 10.0.14393.0StatusaffectedConstraints<10.0.14393.4530
- Version
-
- Version 10.0.14393.0StatusaffectedConstraints<10.0.14393.4530
- Version
-
- Version 10.0.17763.0StatusaffectedConstraints<10.0.17763.2061
- Version
-
- Version 10.0.17763.0StatusaffectedConstraints<10.0.17763.2061
- Version
-
- Version 10.0.0StatusaffectedConstraints<10.0.19041.1110
- Version
-
- Version 10.0.0StatusaffectedConstraints<10.0.19042.1110
- Version
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Microsoft | Windows 10 Version 1507 | n/a |
| |||||||||
| Microsoft | Windows 10 Version 1607 | n/a |
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| Microsoft | Windows 10 Version 1809 | n/a |
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| Microsoft | Windows 10 Version 1909 | n/a |
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| Microsoft | Windows 10 Version 2004 | n/a |
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| Microsoft | Windows 10 Version 20H2 | n/a |
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| Microsoft | Windows 10 Version 21H1 | n/a |
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| Microsoft | Windows 7 | n/a |
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| Microsoft | Windows 7 Service Pack 1 | n/a |
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| Microsoft | Windows 8.1 | n/a |
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| Microsoft | Windows Server 2008 R2 Service Pack 1 | n/a |
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| Microsoft | Windows Server 2008 R2 Service Pack 1 (Server Core installation) | n/a |
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| Microsoft | Windows Server 2008 Service Pack 2 | n/a |
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| Microsoft | Windows Server 2008 Service Pack 2 (Server Core installation) | n/a |
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| Microsoft | Windows Server 2012 | n/a |
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| Microsoft | Windows Server 2012 (Server Core installation) | n/a |
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| Microsoft | Windows Server 2012 R2 | n/a |
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| Microsoft | Windows Server 2012 R2 (Server Core installation) | n/a |
| |||||||||
| Microsoft | Windows Server 2016 | n/a |
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| Microsoft | Windows Server 2016 (Server Core installation) | n/a |
| |||||||||
| Microsoft | Windows Server 2019 | n/a |
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| Microsoft | Windows Server 2019 (Server Core installation) | n/a |
| |||||||||
| Microsoft | Windows Server version 2004 | n/a |
| |||||||||
| Microsoft | Windows Server version 20H2 | n/a |
|
OR
- n/a
- 20h2
- 21h1
- 1607
- 1809
- 1909
- 2004
- n/a
- n/a
- n/a
- n/a
- n/a
- n/a
- n/a
- n/a
- 20h2
- 2004
- n/a
No data.
No Red Hat product state for this CVE.
No package ranges for this CVE.
Remediation
No remediation recorded yet.
Metrics
No CVSS v4.0 score for this CVE.
5.5 MEDIUM NVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
Attack Vector Local
Attack Complexity Low
Privileges Required Low
User Interaction None
Scope Unchanged
Confidentiality Impact None
Integrity Impact High
Availability Impact None
2 other sources (CVE.org, NVD) ▾
6.2 MEDIUM CVE.org
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N/E:U/RL:O/RC:C
Attack Vector Local
Attack Complexity Low
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality Impact None
Integrity Impact High
Availability Impact None
Exploit Maturity Unreported
6.2 MEDIUM NVD
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Attack Vector Local
Attack Complexity Low
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality Impact None
Integrity Impact High
Availability Impact None
No CVSS v3.0 score for this CVE.
2.1 LOW NVD
AV:L/AC:L/Au:N/C:N/I:P/A:N
Access Vector Local
Access Complexity Low
Authentication None
Confidentiality Impact None
Integrity Impact Partial
Availability Impact None
This CVE is not in the KEV list.
No CISA SSVC assessment for this CVE yet.
0.72% 0.00721
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 1, 2026.
EPSS probability 0.00721
Score over time
2021–2026- EPSS v1
- EPSS v5
- EPSS v2
- EPSS v3
- EPSS v4
Percentile over time
- EPSS v1
- EPSS v5
- EPSS v2
- EPSS v3
- EPSS v4
Table of values (18 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 0.72% (0.00721) | 52.24th | v5 (v2026.06.15) |
| Jun 15, 2026 | 0.63% (0.00629) | 45.18th | v5 (v2026.06.15) |
| Mar 30, 2025 | 0.48% (0.00480) | 62.30th | v4 (v2025.03.14) |
| Mar 29, 2025 | 1.52% (0.01524) | 69.53th | v4 (v2025.03.14) |
| Mar 17, 2025 | 0.39% (0.00393) | 58.17th | v4 (v2025.03.14) |
| Dec 17, 2024 | 51.23% (0.51235) | 97.65th | v3 (v2023.03.01) |
| Mar 29, 2024 | 0.28% (0.00284) | 68.14th | v3 (v2023.03.01) |
| Jan 23, 2024 | 0.25% (0.00254) | 63.35th | v3 (v2023.03.01) |
| Dec 29, 2023 | 0.25% (0.00248) | 62.70th | v3 (v2023.03.01) |
| Mar 7, 2023 | 51.23% (0.51235) | 96.94th | v3 (v2023.03.01) |
| Mar 6, 2023 | 1.15% (0.01150) | 60.47th | v2 (v2022.01.01) |
| Feb 4, 2022 | 1.37% (0.01372) | 45.59th | v2 (v2022.01.01) |
| Feb 3, 2022 | 17.64% (0.17642) | 92.83th | v1 |
| Jan 6, 2022 | 17.64% (0.17642) | 92.74th | v1 |
| Jan 5, 2022 | 4.56% (0.04557) | 86.73th | v1 |
| Jul 17, 2021 | 4.56% (0.04557) | 0.00th | v1 |
| Jul 16, 2021 | 0.42% (0.00416) | 0.00th | v5 (v2026.06.15) |
| Jul 15, 2021 | 0.42% (0.00416) | 0.00th | v1 |
Weaknesses (0)
No CWE recorded.
References (2)
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-33765 vendor-advisorypatch
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-33765 PatchVendor Advisory
| Link | Providers | Tags |
|---|---|---|
| https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-33765 | vendor-advisorypatch | |
| https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-33765 | PatchVendor Advisory |
Change history (0)
No recorded changes yet.
Sources
CVE.org / MITRE
Status PUBLISHED
Assigner microsoft
Published Jul 14, 2021
Updated Aug 10, 2026
Reserved May 28, 2021
Link CVE-2021-33765
CISA Vulnrichment
Updated n/a