Microsoft Internet Explorer Use-After-Free Vulnerability

Added to KEV
2026-05-20
Federal due date
2026-06-03
Vendor
Microsoft
Product
Internet Explorer
EPSS
99.5th percentile (score 0.888, as of 2026-06-08)
NVD CVSS v3.1
8.8 (HIGH)
Ransomware use
Unknown
Upstream
https://nvd.nist.gov/vuln/detail/CVE-2010-0249

CISA short description

Microsoft Internet Explorer contains an use-after-free vulnerability that could allow remote attackers to execute arbitrary code by accessing a pointer associated with a deleted object. The impacted product could be end-of-life (EoL) and/or end-of-service (EoS). Users should discontinue product utilization.

Required action

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

NVD description

Use-after-free vulnerability in Microsoft Internet Explorer 6, 6 SP1, 7, and 8 on Windows 2000 SP4; Windows XP SP2 and SP3; Windows Server 2003 SP2; Windows Vista Gold, SP1, and SP2; Windows Server 2008 Gold, SP2, and R2; and Windows 7 allows remote attackers to execute arbitrary code by accessing a pointer associated with a deleted object, related to incorrectly initialized memory and improper handling of objects in memory, as exploited in the wild in December 2009 and January 2010 during Operation Aurora, aka "HTML Object Memory Corruption Vulnerability."

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.