Actively exploited · Published Nov 12, 2013 · Assigned by microsoft

CVE-2013-3918

High 8.8 Exploited

In plain English

A high-severity out-of-bounds write in Windows from Microsoft. Attackers are actively exploiting it in the wild (listed by CISA on October 6, 2025). The chance it is exploited in the next 30 days is estimated at 73.7% (higher than 99.5% of all known vulnerabilities). Ready-made attack tooling exists: Metasploit. Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Severity (CVSS 3.1)8.8High

Exploit odds (30 days)73.7%top 0.5% of all CVEs

Exploited in the wildYesCISA KEV since Oct 6, 2025

Attack tooling1Metasploit

CISA guidance

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Federal agencies must remediate by Oct 27, 2025.

Official description

The InformationCardSigninHelper Class ActiveX control in icardie.dll in Microsoft Windows XP SP2 and SP3, Windows Server 2003 SP2, Windows Vista SP2, Windows Server 2008 SP2 and R2 SP1, Windows 7 SP1, Windows 8, Windows 8.1, Windows Server 2012 Gold and R2, and Windows RT Gold and 8.1 allows remote attackers to execute arbitrary code or cause a denial of service (out-of-bounds write) via a crafted web page that is accessed by Internet Explorer, as exploited in the wild in November 2013, aka "InformationCardSigninHelper Vulnerability."

Affected products (as reported)

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

Weakness: CWE-787 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

References

TA13-317A third-party-advisory, x_refsource_CERT
http://www.darkreading.com/vulnerability/new-ie-vulnerability-found-in-the-wild-s/240163814/ x_refsource_MISC
MS13-090 vendor-advisory, x_refsource_MS
http://www.fireeye.com/blog/technical/2013/11/new-ie-zero-day-found-in-watering-hole-attack.html x_refsource_MISC
oval:org.mitre.oval:def:19089 vdb-entry, signature, x_refsource_OVAL
https://isc.sans.edu/forums/diary/16985 x_refsource_MISC
http://blogs.technet.com/b/msrc/archive/2013/11/11/activex-control-issue-being-addressed-in-update-tuesday.aspx x_refsource_CONFIRM
https://www.microsoft.com/en-us/msrc/blog/2013/11/technical-details-of-the-targeted-attack-using-ie-vulnerability-cve-2013-3918/ vendor-advisory
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2013-3918 government-resource