CVE-2024-21413
Microsoft Outlook Improper Input Validation Vulnerability
CVSS
9.8
Critical
EPSS
94.7%
p100
KEV
YES
Feb 6, 2025
Exploit Today
80
0-100
Published: Feb 13, 2024 · Last modified: Aug 10, 2026 · CWE-20
94.7%EPSS · 30 days94.7%
2026-09-172026-10-15
Product
Microsoft / Office Outlook
Vulnerability
Microsoft Outlook Improper Input Validation Vulnerability
Added to KEV
Feb 6, 2025
Remediate by
Feb 27, 2025
Known ransomware use
No
Summary description
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.
Required action
Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
Notes
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2024-21413 ; https://nvd.nist.gov/vuln/detail/CVE-2024-21413
Microsoft Outlook Remote Code Execution Vulnerability
- msrc.microsoft.comhttps://msrc.microsoft.com/update-guide/vulnerability/CVE-2024-21413
- msrc.microsoft.comhttps://msrc.microsoft.com/update-guide/vulnerability/CVE-2024-21413
- research.checkpoint.comhttps://research.checkpoint.com/2024/the-risks-of-the-monikerlink-bug-in-microsoft-outlook-and-the-big-picture/
- www.vicarius.iohttps://www.vicarius.io/vsociety/posts/cve-2024-21413-critical-monikerlink-vulnerability-affecting-microsoft-outlook-detection-script
- www.vicarius.iohttps://www.vicarius.io/vsociety/posts/cve-2024-21413-critical-monikerlink-vulnerability-affecting-microsoft-outlook-mitigation-script
- www.cisa.govhttps://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2024-21413
CVECVSSEPSSKEVRExploitTitleMod.
CVE-2026-110916——
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——0kin-openapi is a Go project for handling OpenAPI files. Prior to 0.145.0, openapi3filter.ValidationHandler uses the routers/legacy router, which passes an unsupported or non-canonical HTTP method for an existing static path to openapi3.PathItem.GetOperation. The default branch of GetOperation panics before authentication runs, so an unauthenticated remote client can repeatedly send methods such as PROPFIND or lowercase get to abort connections and generate stack-trace log growth. The specific panic requires an exact static path; a concrete path matched only by a templated route does not reach the same sink. This issue is fixed in version 0.145.0.14hCVE-2026-798377.3 HIG—
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