SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2021-26411

Microsoft Internet Explorer Memory Corruption Vulnerability

KEVHIGH 8.8EPSS 80.8%

Does this matter?

Known to be exploited in the wild (CISA KEV, CISA remediation deadline 17 November 2021). Treat as an emergency change: patch or isolate now, then hunt for prior compromise.

Description

Internet Explorer Memory Corruption Vulnerability

CVSS 3.1
8.8 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:H/A:L
EPSS
80.77% probability · 100th percentile
CISA KEV
Listed 3 November 2021 · due 17 November 2021 · used in ransomware campaigns
Weakness
CWE-416
Affected
microsoft/edge · microsoft/internet explorer
Source
secure@microsoft.com

CISA notes

Apply updates per vendor instructions. https://nvd.nist.gov/vuln/detail/CVE-2021-26411

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.