Microsoft Internet Explorer Memory Corruption Vulnerability

HIGH 8.8EXPLOITED (CISA KEV)CVE-2021-26411 · Published 11/03/2021 · updated 01/10/2026

Microsoft Internet Explorer Memory Corruption Vulnerability. Actively exploited: CISA added this vulnerability to its Known Exploited Vulnerabilities catalog on 03/11/2021. Patch affected systems as an emergency. It is known to be used in ransomware campaigns.

Package	Affected versions	Patched versions
internet explorer microsoft	`= 11= 9`	No fix yet

Description

Internet Explorer Memory Corruption Vulnerability

References

msrc.microsoft.com/update-guide/vulnerability/CVE-2021-26411 · Patch
portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-26411 · Patch
cisa.gov/known-exploited-vulnerabilities-catalog · US Government Resource
CISA KEV · CVE-2021-26411

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