Vulnerability record

CVE-2010-3962

Microsoft Internet Explorer Uninitialized Memory Corruption Vulnerability

HighExploitation confirmedCISA KEV

What should I do?

This vulnerability is in the CISA Known Exploited Vulnerabilities catalog: attackers are using it. If you run Internet Explorer, fix it now.

CISA 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.

US federal civilian agencies must remediate by Oct 27, 2025.

Patch status

Official fix available since Sep 30, 2026

Apply the vendor's update to every affected system. Check the fixed-in versions below where known.

Basis: NVD patch reference

Description

Use-after-free vulnerability in Microsoft Internet Explorer 6, 7, and 8 allows remote attackers to execute arbitrary code via vectors related to Cascading Style Sheets (CSS) token sequences and the clip attribute, aka an "invalid flag reference" issue or "Uninitialized Memory Corruption Vulnerability," as exploited in the wild in November 2010.

Source: NIST National Vulnerability Database. Official vulnerability data, reproduced as published.

Affected products

Products affected by this vulnerability, with versions and the source of each entry
Product	Vendor	Affected versions	Source
Internet Explorer	Microsoft	6; 7; 8	KEV

Sources: KEV = CISA Known Exploited Vulnerabilities catalog.

Intelligence timeline

Developments from the last 30 days, newest first.

CVSS scoredUpdateKEVSep 30, 2026
CVE-2010-3962 scored CVSS 8.1: Microsoft Internet Explorer, Microsoft Internet Explorer Uninitialized Memory Corruption Vulnerability
CISA lists this as exploited in the wild. Unpatched Internet Explorer systems are exposed to active attacks now.
Basis: NIST National Vulnerability Database
Patch releasedUpdateKEVSep 30, 2026
Patch released for CVE-2010-3962: Microsoft Internet Explorer, Microsoft Internet Explorer Uninitialized Memory Corruption Vulnerability
An official fix is now available for Microsoft Internet Explorer. This vulnerability is being exploited, so apply it promptly.
Basis: NVD patch reference

1 earlier event is available with a subscription. See plans.

Coverage

We have not published a story about this vulnerability yet.

References

learn.microsoft.com https://learn.microsoft.com/en-us/security-updates/SecurityAdvisories/2010/2458511?redirectedfrom=MSDN
nvd.nist.gov https://nvd.nist.gov/vuln/detail/CVE-2010-3962
blogs.technet.com http://blogs.technet.com/b/msrc/archive/2010/11/02/microsoft-releases-security-advisory-2458511.aspx
secunia.com http://secunia.com/advisories/42091
exploit-db.com http://www.exploit-db.com/exploits/15418
exploit-db.com http://www.exploit-db.com/exploits/15421
kb.cert.org http://www.kb.cert.org/vuls/id/899748
microsoft.com http://www.microsoft.com/technet/security/advisory/2458511.mspx
securityfocus.com http://www.securityfocus.com/bid/44536
securitytracker.com http://www.securitytracker.com/id?1024676
symantec.com http://www.symantec.com/connect/blogs/new-ie-0-day-used-targeted-attacks
us-cert.gov http://www.us-cert.gov/cas/techalerts/TA10-348A.html
vupen.com http://www.vupen.com/english/advisories/2010/2880
docs.microsoft.com https://docs.microsoft.com/en-us/security-updates/securitybulletins/2010/ms10-090
exchange.xforce.ibmcloud.com https://exchange.xforce.ibmcloud.com/vulnerabilities/62962
oval.cisecurity.org https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A12279
cisa.gov https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2010-3962