CVE-2014-1776 Microsoft Internet Explorer Memory Corruption

Exploited in the wild Critical 9.8 Published 27 Apr 2014 Updated 22 Oct 2025

Remote attackers can execute arbitrary code or cause denial of service in Internet Explorer via a use-after-free vulnerability in the CMarkup::IsConnectedToPrimaryMarkup function.

Exploited in the wild: Since 28 Jan 2022
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: None listed

What is CVE-2014-1776?

CVE-2014-1776 is a critical use after free vulnerability in Microsoft Internet Explorer, published on 27 Apr 2014. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

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."

Weakness: CWE-416

Which versions are affected by CVE-2014-1776?

It affects 1 product.

Products include Microsoft Internet Explorer.

How do I fix CVE-2014-1776?

No fix has been published for CVE-2014-1776 yet. Limit exposure of the affected software until one is available. US federal agencies must fix it by 28 Jul 2022.

Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.

Is CVE-2014-1776 being exploited?

Yes. Attackers have exploited CVE-2014-1776 in the wild since at least 28 Jan 2022.

All Microsoft Internet Explorer vulnerabilities

Sources

Also known as GHSA-44fv-7jv8-5cpp.