CVE-2021-27059
MediumExploitedPublic exploitMicrosoft Office Remote Code Execution Vulnerability
Published Mar 12, 2021 · Updated Aug 19, 2026
Key Facts
Patch immediately- CVE-2021-27059 is a medium-severity vulnerability (CVSS 6.5 v3.1) affecting Excel (Microsoft), Office (Microsoft), Office 2013 (Microsoft) and 3 more products.
- It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Mar 12, 2021. Public exploit code is available.
- EPSS estimates a 6.1% probability of exploitation in the next 30 days.
- Fixed versions are available, including Excel 14.0.7266.5000, Excel publication, Office publication.
- Brandefense priority: patch immediately, because it is listed as exploited in the wild.
CVSS v3.1
6.5
CVSS:3.1/AV:L/AC:L/PR:H/UI:R/S:U/C:H/I:H/A:H
EPSS (30-day exploit likelihood)
6.1%
Higher than 93.3% of all scored CVEs
Exploited in the wild
Yes
4 catalog listings
Public exploit code
Available
Proof-of-concept or weaponized module
Get the full CVE-2021-27059 brief as a PDF
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Description
Microsoft Office Remote Code Execution Vulnerability
Known-Exploited Catalog Listings
| Catalog | Added | Remediation due | Ransomware use |
|---|---|---|---|
| CISA KEV | Nov 3, 2021 | Nov 17, 2021 | Not reported |
| Industry KEV feed | Mar 12, 2021 | Nov 17, 2021 | Not reported |
| CIRCL KEV | Nov 3, 2021 | Nov 17, 2021 | Not reported |
| ENISA EUVD | Nov 3, 2021 | n/a | Not reported |
Required action: Apply updates per vendor instructions.
Affected Products
17 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| ExcelMicrosoft | 2010-sp2 | publication |
| OfficeMicrosoft | 2010-sp2, 2013-sp1, 2016 | publication |
| Office 2013Microsoft | See advisory | n/a |
| Office 2016Microsoft | >= 16.0.0 | 16.0.5134.1000 |
| Microsoft Office 2010 Service Pack 2 | >= 13.0.0.0 | 14.0.7266.5000 |
Patched Releases
Excel
14.0.7266.5000, publication
Office
publication
Microsoft Office 2010 Service Pack 2
14.0.7266.5000
Microsoft Office 2013 Service Pack 1
publication
Office 2016
16.0.5134.1000
Timeline
Publicly disclosed
Mar 12, 2021
Added to Industry KEV feed
Mar 12, 2021
Added to CISA KEV
Nov 3, 2021
Added to CIRCL KEV
Nov 3, 2021
Added to ENISA EUVD
Nov 3, 2021
Last updated
Aug 19, 2026
References
- advisoryhttps://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2021-24108
- advisoryhttps://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2021-26861
- advisoryhttps://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2021-26867
- advisoryhttps://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2021-26877
- advisoryhttps://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2021-26881
FAQ
Common Questions.
Microsoft Office Remote Code Execution Vulnerability
Affected: Excel (Microsoft) versions 2010-sp2; Office (Microsoft) versions 2010-sp2, 2013-sp1, 2016; Office 2013 (Microsoft), among others. The full list is in the CVE brief.
It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Mar 12, 2021.
Yes. It was added on Nov 3, 2021 with a federal remediation due date of Nov 17, 2021.
Public exploit code is available.
Fixed versions are available, including Excel 14.0.7266.5000, Excel publication, Office publication.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.
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