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Vulnerability record · CVE-2021-38655 · published 15 September 2021
CVE-2021-38655: Microsoft 365 apps use after free vulnerability
Microsoft · 365 Apps
Microsoft Excel Remote Code Execution Vulnerability
7.8 CVSS 3.1 High EPSS 6.3% · top 6.6% CWE-416 · Use after free
7.8CVSS 3.1 base score, v2 6.8
6.3%EPSS exploitation probability, 30 days
NoNot in CISA KEV
5Affected product versions listed by NVD
3References
10 Aug 2026Last modified by NVD
Description
Microsoft Excel Remote Code Execution Vulnerability
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Affected products
5 vulnerable configurations from NVD's CPE data, grouped by vendor and product.
References
| Link | Tags |
|---|---|
| https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-38655 | |
| https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-38655 | PatchVendor Advisory |
| https://www.zerodayinitiative.com/advisories/ZDI-21-1080/ | Third Party AdvisoryVDB Entry |
Track CVE-2021-38655 inside VULONE
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Source: NIST National Vulnerability Database (record CVE-2021-38655), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.
