What is CVE-2010-3962?

CVE-2010-3962 is a high-severity vulnerability in Microsoft Internet Explorer, classified under Use After Free. CVSS score: 8.1/10. Published 2010-11-05.

How severe is CVE-2010-3962?

High severity. CVSS v3 base score is 8.1 out of 10.

Is CVE-2010-3962 known to be exploited?

Yes. CVE-2010-3962 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2025-10-06), indicating it is being actively exploited. 3 public proof-of-concept repositories are indexed.

Use After Free in Microsoft Internet Explorer

CVE-2010-3962

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.

Vulnerability class: Use-After-Free

Published 2010-11-05 · last modified 2026-06-16.

CVSS v3 metric

CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.968 (99.9th percentile), scored 2026-10-08.

Very high probability of exploitation in the next 30 days — among the top 0.1% most-likely-to-be-exploited CVEs. 100th percentile — 99.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.968 · newest: 0.968 · change: 0.000

Affected products

Microsoft Internet Explorer — versions 6, 7, 8
Microsoft Windows 7
Microsoft Windows Server 2003
Microsoft Windows Server 2008 — versions r2
Microsoft Windows Vista
Microsoft Windows Xp

Weakness classification (CWE)

CWE-416 — Use After Free

CISA KEV (Known Exploited Vulnerabilities)

This CVE is on the CISA KEV catalog, added on 2025-10-06. CISA KEV inclusion means CISA has confirmed in-the-wild exploitation; US federal agencies are required to remediate within a published due date.

BOD 22-01 due date: 2025-10-27.

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.

Public proof-of-concept exploits

References

www.securityfocus.com/bid/44536 (VDB Entry, Third Party Advisory, vdb-entry, Broken Link)
www.us-cert.gov/cas/techalerts/TA10-348A.html (US Government Resource, Third Party Advisory, third-party-advisory)
docs.microsoft.com/en-us/security-updates/securitybulletins/2010/ms10-090 (vendor-advisory, Patch, Vendor Advisory)
www.kb.cert.org/vuls/id/899748 (US Government Resource, Third Party Advisory, third-party-advisory)
secunia.com/advisories/42091 (Broken Link, Vendor Advisory, third-party-advisory)
www.vupen.com/english/advisories/2010/2880 (vdb-entry, Broken Link, Vendor Advisory)
www.microsoft.com/technet/security/advisory/2458511.mspx (Patch, Vendor Advisory)
www.securitytracker.com/id (VDB Entry, Third Party Advisory, vdb-entry, Broken Link)
www.exploit-db.com/exploits/15421 (VDB Entry, Third Party Advisory, exploit)
www.symantec.com/connect/blogs/new-ie-0-day-used-targeted-attacks (Not Applicable)

Frequently asked questions

What is CVE-2010-3962?: CVE-2010-3962 is a high-severity vulnerability in Microsoft Internet Explorer, classified under Use After Free. CVSS score: 8.1/10. Published 2010-11-05.
How severe is CVE-2010-3962?: High severity. CVSS v3 base score is 8.1 out of 10.
Is CVE-2010-3962 known to be exploited?: Yes. CVE-2010-3962 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2025-10-06), indicating it is being actively exploited. 3 public proof-of-concept repositories are indexed.