Microsoft Office Trust Center Spoofing Vulnerability
Summary
| CVE | CVE-2021-43255 |
|---|---|
| State | PUBLISHED |
| Assigner | microsoft |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2021-12-15 15:15:10 UTC |
| Updated | 2026-05-19 18:38:59 UTC |
| Description | Microsoft Office Trust Center Spoofing Vulnerability |
Risk And Classification
Primary CVSS: v3.1 5.5 MEDIUM from [email protected]
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
EPSS: 0.017780000 probability, percentile 0.829380000 (date 2026-05-26)
Problem Types: NVD-CWE-noinfo | Spoofing
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | [email protected] | Primary | 5.5 | MEDIUM | CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N |
| 3.1 | [email protected] | Secondary | 5.5 | MEDIUM | CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N |
| 3.1 | CNA | CVSS | 5.5 | MEDIUM | CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N/E:U/RL:O/RC:C |
| 2.0 | [email protected] | Primary | 4.3 | AV:N/AC:M/Au:N/C:N/I:P/A:N |
CVSS v3.1 Breakdown
Attack Vector
LocalAttack Complexity
LowPrivileges Required
NoneUser Interaction
RequiredScope
UnchangedConfidentiality
NoneIntegrity
HighAvailability
NoneCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
CVSS v2.0 Breakdown
Access Vector
NetworkAccess Complexity
MediumAuthentication
NoneConfidentiality
NoneIntegrity
PartialAvailability
NoneAV:N/AC:M/Au:N/C:N/I:P/A:N
NVD Known Affected Configurations (CPE 2.3)
| Type | Vendor | Product | Version | Update | Edition | Language |
|---|---|---|---|---|---|---|
| Application | Microsoft | 365 Apps | - | All | All | All |
| Application | Microsoft | 365 Apps | - | All | All | All |
| Application | Microsoft | Office | 2013 | sp1 | All | All |
| Application | Microsoft | Office | 2013 | sp1 | All | All |
| Application | Microsoft | Office | 2013_rt | sp1 | All | All |
| Application | Microsoft | Office | 2016 | All | All | All |
| Application | Microsoft | Office | 2016 | All | All | All |
| Application | Microsoft | Office | 2019 | All | All | All |
| Application | Microsoft | Office | 2019 | All | All | All |
| Application | Microsoft | Office Long Term Servicing Channel | 2021 | All | All | All |
| Application | Microsoft | Office Long Term Servicing Channel | 2021 | All | All | All |
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Microsoft | Microsoft Office LTSC 2021 | affected 16.0.1 https://aka.ms/OfficeSecurityReleases custom | x64-based Systems, 32-bit Systems |
| CNA | Microsoft | Microsoft Office 2019 | affected 19.0.0 https://aka.ms/OfficeSecurityReleases custom | 32-bit Systems, x64-based Systems |
| CNA | Microsoft | Microsoft 365 Apps For Enterprise | affected 16.0.1 https://aka.ms/OfficeSecurityReleases custom | 32-bit Systems, x64-based Systems |
| CNA | Microsoft | Microsoft Office 2016 | affected 16.0.0 16.0.5254.1001 custom | 32-bit Systems, x64-based Systems |
| CNA | Microsoft | Microsoft Office 2013 Service Pack 1 | affected 15.0.0 15.0.5407.1000 custom | ARM64-based Systems, 32-bit Systems, x64-based Systems |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| Security Update Guide - Microsoft Security Response Center | af854a3a-2127-422b-91ae-364da2661108 | portal.msrc.microsoft.com | Patch, Vendor Advisory |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
Legacy QID Mappings
- 110396 Microsoft Office Security Update for December 2021