known ransomware use

Microsoft Internet Explorer Use-After-Free Vulnerability

Added to KEV
2022-03-28
Federal due date
2022-04-18
Vendor
Microsoft
Product
Internet Explorer
EPSS
99.7th percentile (score 0.924, as of 2026-06-08)
NVD CVSS v3.1
Ransomware use
Known
Upstream
https://nvd.nist.gov/vuln/detail/CVE-2013-2551

CISA short description

Use-after-free vulnerability in Microsoft Internet Explorer allows remote attackers to execute remote code via a crafted web site that triggers access to a deleted object.

Required action

Apply updates per vendor instructions.

EPSS percentile is the FIRST.org exploit-probability ranking as of the date noted above; it moves daily. CVSS reflects NVD's analysis at time of publication.