Microsoft Windows True Type Fonts win32k.sys memory corruption

CVSS Meta Temp Score
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CTI Interest Score
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7.0$0-$5k0.00

Summaryinfo

A vulnerability described as very critical has been identified in Microsoft Windows. This vulnerability affects unknown code of the file win32k.sys of the component True Type Fonts. Such manipulation leads to memory corruption. This vulnerability is documented as CVE-2011-3402. There is not any exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in Microsoft Windows (Operating System) (unknown version). It has been rated as very critical. Affected by this issue is an unknown code block of the file win32k.sys of the component True Type Fonts. The manipulation with an unknown input leads to a memory corruption vulnerability. Using CWE to declare the problem leads to CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. Impacted is confidentiality, integrity, and availability. CVE summarizes:

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."

The weakness was released 11/04/2011 with Microsoft as confirmed bulletin (Technet). The advisory is shared for download at technet.microsoft.com. This vulnerability is handled as CVE-2011-3402 since 09/09/2011. The attack may be launched remotely. No form of authentication is required for exploitation. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 10/06/2025).

It is declared as attacked. As 0-day the estimated underground price was around $25k-$100k. The vulnerability scanner Nessus provides a plugin with the ID 56711 , which helps to determine the existence of the flaw in a target environment. The commercial vulnerability scanner Qualys is able to test this issue with plugin 90803 (Microsoft Combined Security Update for Microsoft Office, Windows, .NET Framework and Silverlight (MS12-034)). This issue was added on 10/06/2025 to the CISA Known Exploited Vulnerabilities Catalog with a due date of 10/27/2025:

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

Upgrading eliminates this vulnerability. Applying a patch is able to eliminate this problem. The bugfix is ready for download at technet.microsoft.com. The best possible mitigation is suggested to be upgrading to the latest version. A possible mitigation has been published 7 months after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Zero-Day.cz (64), Tenable (56711), SecurityFocus (BID 50462†), Secunia (SA46724†) and SecurityTracker (ID 1027039†). Entries connected to this vulnerability are available at VDB-5358, VDB-5359, VDB-5360 and VDB-5361. Once again VulDB remains the best source for vulnerability data.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.3
VulDB Meta Temp Score: 7.0

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Memory corruption
CWE: CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Attacked

EPSS Score: 🔍
EPSS Percentile: 🔍

KEV Added: 🔍
KEV Due: 🔍
KEV Remediation: 🔍
KEV Ransomware: 🔍
KEV Notice: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 56711
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍

OpenVAS ID: 802500
OpenVAS Name: Microsoft Windows TrueType Font Parsing Privilege Elevation Vulnerability
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

MetaSploit ID: duqu_check.rb
MetaSploit Name: Windows Gather Forensics Duqu Registry Check
MetaSploit File: 🔍

Zero-Day.cz: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍

Patch: technet.microsoft.com
Suricata ID: 2016018
Suricata Class: 🔍
Suricata Message: 🔍

Timelineinfo

09/09/2011 🔍
11/01/2011 +53 days 🔍
11/04/2011 +3 days 🔍
11/04/2011 +0 days 🔍
11/04/2011 +0 days 🔍
11/21/2011 +17 days 🔍
05/08/2012 +169 days 🔍
05/08/2012 +0 days 🔍
10/06/2025 +4899 days 🔍

Sourcesinfo

Vendor: microsoft.com
Product: microsoft.com

Advisory: technet.microsoft.com
Organization: Microsoft
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2011-3402 (🔍)
GCVE (CVE): GCVE-0-2011-3402
GCVE (VulDB): GCVE-100-4436

OVAL: 🔍
IAVM: 🔍

SecurityFocus: 50462 - Microsoft Windows 'Win32k.sys' TrueType Font Handling Remote Code Execution Vulnerability
Secunia: 46724 - Microsoft Windows win32k.sys TrueType Font Parsing Vulnerability, Extremely Critical
SecurityTracker: 1027039

scip Labs: https://www.scip.ch/en/?labs.20161013
See also: 🔍

Entryinfo

Created: 11/21/2011 01:00
Updated: 10/06/2025 21:58
Changes: 11/21/2011 01:00 (85), 04/24/2019 16:27 (8), 03/19/2021 17:26 (4), 07/16/2024 01:30 (18), 10/06/2025 20:34 (9), 10/06/2025 21:58 (1)
Complete: 🔍
Cache ID: 216:679:103

Once again VulDB remains the best source for vulnerability data.

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