CVE-2021-43255
Status: ModifiedMedium (5.5)—
Microsoft Office Trust Center Spoofing Vulnerability
CVSS
- Version: 3.1
- Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
- Base score: 5.5
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 1.98%
- Percentile among all scored CVEs: 80
- Score date: 10/7/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
Affected technologies (3)
CWEs
- NVD-CWE-noinfo
References
Raw JSON (NVD)
Show
{
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"cveTags": [],
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"timestamp": "2024-07-25T16:03:02.551633Z"
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"exploitabilityScore": 8.6,
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"product": "Microsoft Office 2016",
"versions": [
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"published": "2021-12-15T15:15:10.687",
"references": [
{
"url": "https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-43255",
"tags": [
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"source": "secure@microsoft.com"
},
{
"url": "https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-43255",
"tags": [
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"source": "af854a3a-2127-422b-91ae-364da2661108"
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"vulnStatus": "Modified",
"weaknesses": [
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"type": "Primary",
"source": "nvd@nist.gov",
"description": [
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"value": "NVD-CWE-noinfo"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "Microsoft Office Trust Center Spoofing Vulnerability"
},
{
"lang": "es",
"value": "Una vulnerabilidad de Suplantación de Identidad de Microsoft Office Trust Center"
}
],
"lastModified": "2026-06-17T04:10:44.473",
"configurations": [
{
"nodes": [
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"sourceIdentifier": "secure@microsoft.com"
}