VulnTideExploited vulnerabilities, by vendor. Data as of 28 Oct 2026.
Known exploitedIn CISA's KEV catalog since 3 November 2021Ransomware use: unknown
Microsoft Office

CVE-2021-27059: Microsoft Office Remote Code Execution Vulnerability

Is it exploited?

Yes. CISA added it to the Known Exploited Vulnerabilities catalog on 3 Nov 2021, 237 days after the CVE record was published.

How likely is exploitation in the next 30 days?
6.1%

EPSS score, percentile 93.4 of all scored records

How severe?
7.6 High

CVSS v3.1 base score, given by the CNA

What should I do?

CISA deadline 17 Nov 2021. Apply updates per vendor instructions.

Advisories and patches (1)

Which versions are affected?

Affected

  • from 13.0.0.0 to before 14.0.7266.5000
  • 15.0.0
  • from 16.0.0 to before 16.0.5134.1000

Versions by product

Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

What to do

Required action, set by CISA

Apply updates per vendor instructions.

CISA due date for this action: 17 November 2021.

Advisories and patches

Linked from CISA's catalog entry

Affected products and versions

As listed in the CVE record.

Microsoft Microsoft Office 2010 Service Pack 2
StatusVersions
Affectedfrom 13.0.0.0 to before 14.0.7266.5000
Microsoft Microsoft Office 2013 Service Pack 1
StatusVersions
Affected15.0.0
Microsoft Microsoft Office 2016
StatusVersions
Affectedfrom 16.0.0 to before 16.0.5134.1000

Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

About this vulnerability

Microsoft Office contains an unspecified vulnerability that allows for remote code execution.

Summary: CISA's KEV catalog, as of 28 Oct 2026.

  • CISA added CVE-2021-27059 to its Known Exploited Vulnerabilities (KEV) catalog on 3 Nov 2021.
  • CISA's ransomware flag for this entry is "Unknown": no evidence of ransomware use in the catalog, which is not proof of none.
  • The due date CISA sets for the required action is 17 Nov 2021.
  • The CVE record was published on 11 Mar 2021, 237 days before it was added to KEV.
  • The CVE record carries a CVSS v3.1 base score of 7.6 (High), given by its CNA.
  • FIRST's EPSS model puts the probability of exploitation in the next 30 days at 6.1% (percentile 93.4), as of 28 Oct 2026.
  • CISA's SSVC assessment in the CVE record: exploitation active, automatable no, technical impact total.

Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026. About the data.

Description

Microsoft Office Remote Code Execution Vulnerability

Microsoft Office Remote Code Execution Vulnerability

Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

Timeline

DateEvent
11 Mar 2021CVE record published
3 Nov 2021Added to CISA KEV
17 Nov 2021CISA due date for the required action
19 Aug 2026CVE record last updated

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