9.6

CVE-2021-43905: microsoft 365_copilot

CVSS: 9.6v3.1CriticalAnalyzed
Published 15-12-2021Last modified 28-05-2026
Open JSON

Vulnerability summary

CVE-2021-43905 is a critical (CVSS 9.6) vulnerability in microsoft 365_copilot. EPSS estimates a 2.98% chance of exploitation in the next 30 days, higher than 87% of scored vulnerabilities.

Overall risk
70/100
0100
High · default modelHow is this calculated?
CVSS score
9.6/10
010
Critical · v3.1 (CVE.org)
EPSS score
2.98%
0%100%
Low · +0.16 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 15-12-2021
    PublishedVulnerability first disclosed.
  2. 28-05-2026
    Last modifiedVulnerability information updated.

Description

Microsoft Office app Remote Code Execution Vulnerability

CVSS metrics

3 scores · 2 sources · 2 versions

EPSS trend

Probability

2.98%

Chance of exploitation in the next 30 days

Percentile

87%

Versus all other CVEs

30-day change

+0.16 pp

From 2.82% on 19-09-2026

19-09-202619-10-2026
EPSS score
2.98%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

No weakness data has been published for this record.

Affected systems

Microsoft2 products

1 vendor · 2 products

References

1 links