Cyber Resilience

CVE-2021-27085

Microsoft Internet Explorer 11

CISA KEVActive ExploitationEUVD Exploited
Published
11 March 2021
Modified
30 October 2025
KEV Added
03 November 2021
Patch / advisory
CVSS Score v3.1 8.8
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:H/A:L
EPSS Score 0.037 89th percentile
Risk Priority 88 floored blend · peak EPSS

Summary

CVE-2021-27085 is a high-severity an unspecified weakness vulnerability in Microsoft Internet Explorer. Its CVSS base score is 8.8 (High).

Operationally, ranked in the top 11% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2021-27085 is a remote code execution vulnerability affecting Internet Explorer. It received a CVSS 3.1 base score of 8.8 with the vector AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:H/A:L and is tracked under NVD-CWE-noinfo.

An attacker can exploit the flaw over the network without authentication when a user interacts with specially crafted content, resulting in code execution that crosses security boundaries and produces limited confidentiality impact, high integrity impact, and limited availability impact.

Microsoft has published security guidance and updates addressing the issue through its MSRC advisory portal, while CISA has added CVE-2021-27085 to its catalog of known exploited vulnerabilities.

The vulnerability was publicly disclosed on 11 March 2021.

EU & UK References

Vulnerability Data

Internet Explorer Remote Code Execution Vulnerability

CWE(s)
KEV Date Added
03 November 2021

Related Threats

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Affected Assets

microsoft
internet explorer
11

Mitigating Controls

No mitigating controls mapped yet. The per-CVE control annotator has not reached this CVE.

References