What is CVE-2014-1776?

CVE-2014-1776 is a critical-severity vulnerability in Microsoft Internet Explorer, classified under Use After Free. CVSS score: 9.8/10. Published 2014-04-27.

How severe is CVE-2014-1776?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Is CVE-2014-1776 known to be exploited?

Yes. CVE-2014-1776 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2022-01-28), indicating it is being actively exploited. 17 public proof-of-concept repositories are indexed.

Use After Free in Microsoft Internet Explorer

CVE-2014-1776

Use-after-free vulnerability in Microsoft Internet Explorer 6 through 11 allows remote attackers to execute arbitrary code or cause a denial of service (memory corruption) via vectors related to the CMarkup::IsConnectedToPrimaryMarkup function, as exploited in the wild in April 2014. NOTE: this issue originally emphasized VGX.DLL, but Microsoft clarified that "VGX.DLL does not contain the vulnerable code leveraged in this exploit. Disabling VGX.DLL is an exploit-specific workaround that provides an immediate, effective workaround to help block known attacks."

Vulnerability class: Use-After-Free

Published 2014-04-27 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.827 (99.7th percentile), scored 2026-10-16.

High probability of exploitation in the next 30 days — patch promptly. 100th percentile — 99.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.880 · newest: 0.827 · change: -0.053

Affected products

Microsoft Internet Explorer — versions 6, 7, 8
Microsoft Windows 7
Microsoft Windows 8
Microsoft Windows 8.1
Microsoft Windows Rt
Microsoft Windows Rt 8.1
Microsoft Windows Server 2003
Microsoft Windows Server 2008 — versions r2
Microsoft Windows Server 2012 — versions r2
Microsoft Windows Vista

Weakness classification (CWE)

CWE-416 — Use After Free

CISA KEV (Known Exploited Vulnerabilities)

This CVE is on the CISA KEV catalog, added on 2022-01-28. 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: 2022-07-28.

Required action: Apply updates per vendor instructions.

Public proof-of-concept exploits

References

securitytracker.com/id (VDB Entry, Third Party Advisory, vdb-entry, Broken Link)
www.osvdb.org/106311 (vdb-entry, Broken Link)
docs.microsoft.com/en-us/security-updates/securitybulletins/2014/ms14-021 (vendor-advisory, Patch, Vendor Advisory)
blogs.technet.com/b/srd/archive/2014/04/30/protection-strategies-for-the-securi… (Mitigation, Broken Link)
secunia.com/advisories/57908 (Broken Link, third-party-advisory)
www.signalsec.com/cve-2014-1776-ie-0day-analysis/ (Exploit, Third Party Advisory)
www.fireeye.com/blog/uncategorized/2014/04/new-zero-day-exploit-targeting-inter… (Broken Link)
www.kb.cert.org/vuls/id/222929 (US Government Resource, Third Party Advisory, Mitigation, third-party-advisory)
technet.microsoft.com/library/security/2963983 (Patch, Mitigation, Vendor Advisory)
www.securityfocus.com/bid/67075 (VDB Entry, Third Party Advisory, vdb-entry, Broken Link)

Frequently asked questions

What is CVE-2014-1776?: CVE-2014-1776 is a critical-severity vulnerability in Microsoft Internet Explorer, classified under Use After Free. CVSS score: 9.8/10. Published 2014-04-27.
How severe is CVE-2014-1776?: Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2014-1776 known to be exploited?: Yes. CVE-2014-1776 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2022-01-28), indicating it is being actively exploited. 17 public proof-of-concept repositories are indexed.