Exploitation evidence
Known exploited · CISA KEV listed
Added 2025-02-06. Ransomware campaign use: Unknown.
CISA required action: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
CISA due date: 2025-02-27. This is the catalog’s deadline, not an assessment of your organization’s exposure.
KEV checked 13 Nov 2026, 00:20 Jerusalem · Original catalog ↗Reported products and versions
Microsoft / Microsoft 365 Apps for Enterprise
Default status: Not specified
- affected: 16.0.1 to < https://aka.ms/OfficeSecurityReleases (custom)
Microsoft / Microsoft Office 2016
Default status: Not specified
- affected: 16.0.0 to < 16.0.5435.1001 (custom)
Microsoft / Microsoft Office 2019
Default status: Not specified
- affected: 19.0.0 to < https://aka.ms/OfficeSecurityReleases (custom)
Microsoft / Microsoft Office LTSC 2021
Default status: Not specified
- affected: 16.0.1 to < https://aka.ms/OfficeSecurityReleases (custom)
Fixes and workarounds
No explicit solution text in the downloaded CVE record. Consult the vendor advisory; unaffected version ranges are shown above as reported, not inferred as a patch recommendation.
Sources and related reporting
CVE Program record ↗ · Download tracked evidence as JSON
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2024-21413
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2024-21413
- https://www.vicarius.io/vsociety/posts/cve-2024-21413-critical-monikerlink-vulnerability-affecting-microsoft-outlook-mitigation-script
- https://www.vicarius.io/vsociety/posts/cve-2024-21413-critical-monikerlink-vulnerability-affecting-microsoft-outlook-detection-script
- https://research.checkpoint.com/2024/the-risks-of-the-monikerlink-bug-in-microsoft-outlook-and-the-big-picture/
Observed change timeline
History begins when Egret first downloads each source. It is not the complete upstream CVE history.
12 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-12",
"epss": 0.9466,
"percentile": 0.99858
}10 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-10",
"epss": 0.9466,
"percentile": 0.99857
}09 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-09",
"epss": 0.9466,
"percentile": 0.99857
}08 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-08",
"epss": 0.9466,
"percentile": 0.99857
}07 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-07",
"epss": 0.9466,
"percentile": 0.99857
}06 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-06",
"epss": 0.9466,
"percentile": 0.99857
}06 Nov 2026, 06:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-05",
"epss": 0.9466,
"percentile": 0.99857
}04 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-04",
"epss": 0.9466,
"percentile": 0.99856
}04 Nov 2026, 12:20 Jerusalem · CVE Program record changed
Stored CNA snapshot at this observation.
{
"containers": {
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"content": {
"id": "CVE-2024-21413",
"options": [
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{
"Automatable": "yes"
},
{
"Technical Impact": "total"
}
],
"role": "CISA Coordinator",
"timestamp": "2025-02-07T04:55:29.467185Z",
"version": "2.0.3"
},
"type": "ssvc"
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},
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"title": "CISA ADP Vulnrichment"
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"references": [
{
"url": "https://www.vicarius.io/vsociety/posts/cve-2024-21413-critical-monikerlink-vulnerability-affecting-microsoft-outlook-mitigation-script"
},
{
"url": "https://www.vicarius.io/vsociety/posts/cve-2024-21413-critical-monikerlink-vulnerability-affecting-microsoft-outlook-detection-script"
},
{
"name": "Microsoft Outlook Remote Code Execution Vulnerability",
"tags": [
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],
"url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2024-21413"
},
{
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],
"url": "https://research.checkpoint.com/2024/the-risks-of-the-monikerlink-bug-in-microsoft-outlook-and-the-big-picture/"
}
],
"title": "CVE Program Container",
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"cna": {
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{
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],
"product": "Microsoft Office 2016",
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{
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],
"product": "Microsoft Office 2019",
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{
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],
"product": "Microsoft Office LTSC 2021",
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{
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],
"cpeApplicability": [
{
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},
{
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},
{
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"versionEndExcluding": "https://aka.ms/OfficeSecurityReleases",
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},
{
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],
"datePublic": "2024-02-13T08:00:00.000Z",
"descriptions": [
{
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"value": "Microsoft Outlook Remote Code Execution Vulnerability"
}
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{
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"description": "CWE-20: Improper Input Validation",
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}
]
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],
"providerMetadata": {
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{
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}
],
"title": "Microsoft Outlook Remote Code Execution Vulnerability"
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},
"cveMetadata": {
"assignerOrgId": "f38d906d-7342-40ea-92c1-6c4a2c6478c8",
"assignerShortName": "microsoft",
"cveId": "CVE-2024-21413",
"datePublished": "2024-02-13T18:02:24.799Z",
"dateReserved": "2023-12-08T22:45:21.300Z",
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"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
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}03 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-03",
"epss": 0.9466,
"percentile": 0.99857
}03 Nov 2026, 02:22 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-02",
"epss": 0.9466,
"percentile": 0.99857
}03 Nov 2026, 02:22 Jerusalem · CISA KEV status changed
Stored KEV snapshot at this observation.
{
"cveID": "CVE-2024-21413",
"cwes": [
"CWE-20"
],
"dateAdded": "2025-02-06",
"dueDate": "2025-02-27",
"forensicTriage": "No",
"knownRansomwareCampaignUse": "Unknown",
"notes": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2024-21413 ; https://nvd.nist.gov/vuln/detail/CVE-2024-21413",
"product": "Office Outlook",
"requiredAction": "Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.",
"shortDescription": "Microsoft Outlook contains an improper input validation vulnerability that allows for remote code execution. Successful exploitation of this vulnerability would allow an attacker to bypass the Office Protected View and open in editing mode rather than protected mode.",
"vendorProject": "Microsoft",
"vulnerabilityName": "Microsoft Outlook Improper Input Validation Vulnerability"
}