---
title: "CVE-2013-3918: Microsoft Windows Out-of-Bounds Write Vulnerability"
url: https://erroneo.us/security/cve/CVE-2013-3918/
description: "CVE-2013-3918 (Microsoft Windows): Exploited in the wild (CISA KEV). The InformationCardSigninHelper Class ActiveX control in icardie.dll in Microsoft…"
type: vulnerability-record
section: "Security Digest"
date_published: 2013-11-12
date_modified: 2025-10-22
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2013-3918"
kev: true
cvss: 8.8
epss: 0.73693
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2013-3918: Microsoft Windows Out-of-Bounds Write Vulnerability

**Signal:** Exploited: patch now if you run it. CISA has confirmed exploitation in the wild. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- Yes, if you run Microsoft Windows. CISA added this CVE to its Known Exploited Vulnerabilities catalog on 2025-10-06, which means there is reliable evidence of exploitation in the wild. US federal agencies must remediate by 2025-10-27 ; treat that as the outer limit, not the target.
- EPSS 73.7% , percentile 99: FIRST’s model estimates a 73.7% chance of exploitation activity in the next 30 days, higher than 99% of all scored CVEs (very high). EPSS is a probability, not a verdict.
- Needs a user to click or open something. Phishing makes that realistic, but it is not wormable.

## What it is

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 (CVE record)

- n/a n/a: see advisory

## Severity

- CISA-ADP CVSS 3.1: 8.8 `CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H`

## Exploitation

- CISA KEV: added 2025-10-06; federal due date 2025-10-27. Known ransomware use: Unknown.
- CISA 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.
- CISA SSVC assessment: exploitation active , automatable no , technical impact total .
- FIRST EPSS (model of 2026-10-21): 73.69% probability of exploitation activity in the next 30 days; percentile 99.

## Sources

- [MS13-090](https://docs.microsoft.com/en-us/security-updates/securitybulletins/2013/ms13-090)
- [microsoft.com](https://www.microsoft.com/en-us/msrc/blog/2013/11/technical-details-of-the-targeted-attack-using-ie-vulnerability-cve-2013-3918/)
- [CVE.org record CVE-2013-3918](https://www.cve.org/CVERecord?id=CVE-2013-3918)
- [NVD entry CVE-2013-3918](https://nvd.nist.gov/vuln/detail/CVE-2013-3918)
- [CISA Known Exploited Vulnerabilities catalog entry](https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2013-3918)
- [TA13-317A](http://www.us-cert.gov/ncas/alerts/TA13-317A)
- [darkreading.com](http://www.darkreading.com/vulnerability/new-ie-vulnerability-found-in-the-wild-s/240163814/)
- [fireeye.com](http://www.fireeye.com/blog/technical/2013/11/new-ie-zero-day-found-in-watering-hole-attack.html)
- [oval:org.mitre.oval:def:19089](https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A19089)
- [isc.sans.edu](https://isc.sans.edu/forums/diary/16985)
- [blogs.technet.com](http://blogs.technet.com/b/msrc/archive/2013/11/11/activex-control-issue-being-addressed-in-update-tuesday.aspx)

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Source page: https://erroneo.us/security/cve/CVE-2013-3918/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt