VulnerabilityAnalyzed
CVE-2024-21413
Microsoft Outlook Improper Input Validation Vulnerability
KEVCRITICAL 9.8EPSS 94.7%
Does this matter?
Known to be exploited in the wild (CISA KEV, CISA remediation deadline 27 February 2025). Treat as an emergency change: patch or isolate now, then hunt for prior compromise.
Description
Microsoft Outlook Remote Code Execution Vulnerability
- CVSS 3.1
- 9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 94.66% probability · 100th percentile
- CISA KEV
- Listed 6 February 2025 · due 27 February 2025
- Weakness
- CWE-20
- Affected
- microsoft/365 apps · microsoft/office 2016 · microsoft/office 2019 · microsoft/office long term servicing channel
- Source
- secure@microsoft.com
CISA notes
Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable. https://msrc.microsoft.com/update-guide/vulnerability/CVE-2024-21413 ; https://nvd.nist.gov/vuln/detail/CVE-2024-21413
References
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2024-21413Patch, Vendor Advisory
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2024-21413Patch, Vendor Advisory
- https://research.checkpoint.com/2024/the-risks-of-the-monikerlink-bug-in-microsoft-outlook-and-the-big-picture/Technical Description
- https://www.vicarius.io/vsociety/posts/cve-2024-21413-critical-monikerlink-vulnerability-affecting-microsoft-outlook-detection-scriptExploit
- https://www.vicarius.io/vsociety/posts/cve-2024-21413-critical-monikerlink-vulnerability-affecting-microsoft-outlook-mitigation-scriptMitigation
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2024-21413US Government Resource
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.