How severe is CVE-2021-27085?

CVE-2021-27085 has a CVSS 3.1 base score of 8.8 (HIGH). EPSS estimates a 5.4% probability of exploitation in the next 30 days. It is listed in the CISA Known Exploited Vulnerabilities catalog.

CVE-2021-27085: Internet Explorer Remote Code Execution

CISA Known Exploited Vulnerabilities

Microsoft Internet Explorer Remote Code Execution Vulnerability is confirmed as actively exploited and is listed in the CISA KEV catalog.

Added to KEV

2021-11-03

Remediation due

2021-11-17

Required action
Apply updates per vendor instructions.

CISA notes
https://nvd.nist.gov/vuln/detail/CVE-2021-27085

Description

Internet Explorer Remote Code Execution Vulnerability

Severity

CVSS 3.1 · CNA8.8 HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:H/A:L/E:P/RL:O/RC:C

SSVC · CISA-ADP

Exploitationactive

Automatableno

Technical impactpartial

Affected Products

Vendor	Product	Affected versions
Microsoft	Internet Explorer 11	1.0.0 to <10.0.17134.2087

References

2 Links

Vendor advisories

Internet Explorer Remote Code Execution Vulnerability

Other references

https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-27085

Record Details

Published

2021-03-11

Last updated

2026-08-19

Assigner (CNA)

microsoft

Credited to

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CVE record data © The MITRE Corporation, used under the CVE Terms of Use. Exploited-in-the-wild data from the CISA Known Exploited Vulnerabilities catalog (CC0). Exploit prediction scores by FIRST EPSS (first.org/epss). This site is not endorsed or certified by MITRE, NVD, CISA, or FIRST.