How severe is CVE-2021-27085?

CVE-2021-27085 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity high, and availability low.

Is CVE-2021-27085 being actively exploited?

Yes. CVE-2021-27085 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2021-11-03, which means active exploitation has been confirmed. It should be prioritised for remediation.

What products are affected by CVE-2021-27085?

CVE-2021-27085 affects Microsoft Internet Explorer. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-27085?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.

Does CVE-2021-27085 have an EU (EUVD) identifier?

Yes. CVE-2021-27085 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-13856. It is also flagged as exploited in the EUVD (since 2021-11-03).

When was CVE-2021-27085 published?

CVE-2021-27085 was published on 2021-03-11 and last updated on 2026-06-17.

CVE-2021-27085

CVE-2021-27085 is a high-severity vulnerability in Microsoft Internet Explorer with a CVSS 3.x base score of 8.8. It is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, confirming it has been exploited in the wild (added 2021-11-03).

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 7.6
EPSS exploit prediction: 4% (88th percentile)
Actively exploited: Yes — listed in CISA KEV (added 2021-11-03)
EU (EUVD) id: EUVD-2021-13856
EU exploitation: Flagged exploited in the ENISA EU Vulnerability Database (since 2021-11-03)
Affected product: Microsoft Internet Explorer
Published: 2021-03-11
Last modified: 2026-06-17

Description

Internet Explorer Remote Code Execution Vulnerability

Frequently asked questions

What is CVE-2021-27085?: Internet Explorer Remote Code Execution Vulnerability
How severe is CVE-2021-27085?: CVE-2021-27085 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity high, and availability low.
Is CVE-2021-27085 being actively exploited?: Yes. CVE-2021-27085 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2021-11-03, which means active exploitation has been confirmed. It should be prioritised for remediation.
What products are affected by CVE-2021-27085?: CVE-2021-27085 affects Microsoft Internet Explorer. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-27085?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.
Does CVE-2021-27085 have an EU (EUVD) identifier?: Yes. CVE-2021-27085 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-13856. It is also flagged as exploited in the EUVD (since 2021-11-03).
When was CVE-2021-27085 published?: CVE-2021-27085 was published on 2021-03-11 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:microsoft:internet_explorer:11:-:*:*:*:*:*:*

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