CVE-2021-27085
Published: November 3, 2021
Official Description
Microsoft Internet Explorer contains an unspecified vulnerability that allows for remote code execution.
CISA KEV Advisory
Microsoft Internet Explorer Remote Code Execution Vulnerability
Microsoft Internet Explorer contains an unspecified vulnerability that allows for remote code execution.
Apply updates per vendor instructions.
Risk Analysis
This high-severity vulnerability in Microsoft Internet Explorer allows for remote code execution, meaning an attacker could run arbitrary code on a vulnerable system. Its presence in CISA's KEV catalog and an EPSS score of 0.01619 highlight its confirmed exploitation and a significant likelihood of further attacks.
This vulnerability is actively being exploited in the wild, indicating its current use by threat actors. No specific exploit details are provided.
It is critical to apply all available security updates for Microsoft Internet Explorer. Consider migrating to a more modern, supported browser if possible.
Technical Analysis
CVE-2021-27085 requires local access, meaning attackers must already have a foothold on the target system.
Exploitation requires some privileges, which limits the exposure to scenarios where an attacker has already gained initial access.
CISA has added CVE-2021-27085 to the Known Exploited Vulnerabilities (KEV) catalog, confirming active exploitation in the wild. U.S. federal agencies are required to patch this within the mandated timeframe, and all organizations should treat remediation as urgent.
Affected Vendors & Products
Exploit & PoC Resources
All References (1)
Quick Facts
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2021-27085 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts
- !CISA KEV: Federal agencies must patch per BOD 22-01 timeline
- !Active exploitation confirmed — treat as P1