CVE-2012-4969 — Microsoft Internet Explorer Use-After-Free Vulnerability

Use-after-free vulnerability in the CMshtmlEd::Exec function in mshtml.dll in Microsoft Internet Explorer 6 through 9 allows remote attackers to execute arbitrary code via a crafted web site, as exploited in the wild in September 2012.

01What is this vulnerability?

Use-after-free vulnerability in the CMshtmlEd::Exec function in mshtml.dll in Microsoft Internet Explorer 6 through 9 allows remote attackers to execute arbitrary code via a crafted web site, as exploited in the wild in September 2012.

02Affected products

Vendor	Product	Versions
n	a / n/a	n/a

03Active exploitation status

Yes — actively exploited. Added to the CISA KEV catalog on 2022-06-08. Ransomware use: Unknown.

04Recommended remediation

• Patch to a fixed version listed in the vendor advisory (see references below).
• Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
• Hunt historical logs for exploitation indicators — see Detection signatures below.

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Open the Sigma generator with a pre-filled prompt for this CVE to draft a starting detection in your stack of choice:

Open in Sigma generator →

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

• Published: 2012-09-18T10:00:00.000Z
• Last modified: 2025-10-22T00:05:46.392Z
• Added to CISA KEV: 2022-06-08
• BOD 22-01 due: 2022-06-22

09References

• www.us-cert.gov — http://www.us-cert.gov/cas/techalerts/TA12-265A.html
• www.kb.cert.org — http://www.kb.cert.org/vuls/id/480095
• oval.cisecurity.org — https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3…
• www.us-cert.gov — http://www.us-cert.gov/cas/techalerts/TA12-262A.html
• www.securityweek.com — http://www.securityweek.com/new-internet-explorer-zero-day-being-exploited-wild
• technet.microsoft.com — http://technet.microsoft.com/security/advisory/2757760
• www.us-cert.gov — http://www.us-cert.gov/cas/techalerts/TA12-255A.html
• blog.vulnhunt.com — http://blog.vulnhunt.com/index.php/2012/09/17/ie-execcommand-fuction-use-after-f…
• dev.metasploit.com — http://dev.metasploit.com/redmine/projects/framework/repository/entry/modules/ex…
• www.securitytracker.com — http://www.securitytracker.com/id?1027538
• eromang.zataz.com — http://eromang.zataz.com/2012/09/16/zero-day-season-is-really-not-over-yet/