CVE-2011-3402
Unspecified vulnerability in the TrueType font parsing engine in win32k.sys in the kernel-mode drivers in Microsoft Windows XP SP2 and SP3, Windows Server 2003 SP2, Windows Vista SP2, Windows Server 2008 SP2, R2, and R2 SP1, and Windows 7 Gold and SP1 allows remote attackers to execute arbitrary code via crafted font data in a Word document or web page, as exploited in the wild in November 2011 by Duqu, aka "TrueType Font Parsing Vulnerability."
do firstApply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Can a WAF block it? No. The vulnerability is triggered by crafted font data delivered in a Word document or web page, which looks like normal content to a web application firewall and does not contain unusual patterns that can be reliably filtered.
Also consider: patch
Based on an AI reading of the CVE description, and no vendor rule found yet. We check Cloudflare, AWS, Google Cloud Armor and Azure; for Akamai, Imperva, Fastly, F5, ask your vendor.
Is CVE-2011-3402 being exploited?
Yes. CVE-2011-3402 appears in CISA's Known Exploited Vulnerabilities catalog, which means exploitation in the wild has been confirmed and reported. Treat it as active rather than theoretical, and patch it ahead of higher-scoring vulnerabilities that carry no exploitation evidence.
How severe is CVE-2011-3402?
CVE-2011-3402 is rated High with a CVSS score of 8.8. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2011-3402?
Yes. A fix has been recorded for CVE-2011-3402. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2011-3402 affect?
CVE-2011-3402 affects microsoft:windows_7, microsoft:windows_server_2003, microsoft:windows_server_2008, microsoft:windows_vista, and 1 further product or version. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
public exploits
Detection templates only, no public exploit found: 1 Metasploit module
- post/windows/gather/forensics/duqu_check · post · normal
Listed so you can judge urgency, not as a recommendation to run anything. GitHub “proofs of concept” are unvetted: some are fake or carry malware. Exploit-DB marks the entries its staff verified.
cisa ssvc
- exploitation
- active
- automatable
- no
- technical impact
- total
Assessed by CISA 4 Oct 2025 (SSVC 2.0.3).
timeline
- 4 Nov 2011Published
- 4 Oct 2025CISA SSVC assessment: exploitation active · 5,082 days (about 14 years) later
- 6 Oct 2025Added to CISA KEV (exploited in the wild) · 2 days later
- 22 Oct 2025CVE record last updated · 16 days later
- 27 Oct 2025CISA remediation due date (US federal agencies) · 5 days later
- 2 Nov 2026Analysed by vulneraibility.com · 372 days (about 1 year) later
- Advisorysecunia.com /advisories/49121
- Advisoryus-cert.gov /cas/techalerts/TA12-164A.html
- Advisorysecunia.com /advisories/49122
- Advisorydocs.microsoft.com /en-us/security-updates/securitybulletins/2011/ms11-087
- Advisoryus-cert.gov /cas/techalerts/TA11-347A.html
- Advisorydocs.microsoft.com /en-us/security-updates/securitybulletins/2012/ms12-034
- Advisorydocs.microsoft.com /en-us/security-updates/securitybulletins/2012/ms12-039
- Advisoryus-cert.gov /cas/techalerts/TA12-129A.html
Show 13 more
- Linkoval.cisecurity.org /repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A15645
- Linkblogs.mcafee.com /mcafee-labs/the-day-of-the-golden-jackal-%E2%80%93-further-tales-of-the-stuxnet
- Linksecuritytracker.com /id?1027039
- Linksymantec.com /content/en/us/enterprise/media/security_response/whitepapers/w32_duqu_the_precu
- Linkoval.cisecurity.org /repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A13998
- Linkus-cert.gov /control_systems/pdf/ICS-ALERT-11-291-01E.pdf
- Linksecurelist.com /en/blog/208193197/The_Mystery_of_Duqu_Part_Two
- Linktechnet.microsoft.com /security/advisory/2639658
- Linkoval.cisecurity.org /repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A15290
- Linkisc.sans.edu /diary/Duqu+Mitigation/11950
- Linksymantec.com /connect/w32-duqu_status-updates_installer-zero-day-exploit
- Linkblogs.technet.com /b/msrc/archive/2011/11/03/microsoft-releases-security-advisory-2639658.aspx
- Linkcisa.gov /known-exploited-vulnerabilities-catalog?field_cve=CVE-2011-3402
sources
- CVE List (CVE.org): description, affected versions, references; CVE Terms of Use
- NVD: CVSS and CPE data
- CISA KEV catalog: exploitation, date added, due date
- CISA Vulnrichment (ADP): SSVC decision points
- FIRST EPSS: exploit probability and percentile
- Metasploit Framework: exploit and scanner modules
- Summary, impact and triage tags: written by our AI analysis pipeline from the sources above. Check them against the sources.