🟢 CVE-2011-3402

CVE-2011-3402 is a critical vulnerability in the TrueType font parsing engine of the Windows kernel (`win32k.sys`) that gained significant notoriety in late 2011. Below is a summary of the requested information.

Overview and Impact

• Vulnerability Type: A kernel-mode vulnerability in the TrueType font parsing engine?Name=Exploit%3AWin32%2FCVE-2011-3402?kagi_q=CVE-2011-3402+details+exploitation+threat+actor+ransomware.
• Impact: Successful exploitation allows an attacker to execute arbitrary code with kernel-mode privileges?Name=Exploit%3AWin32%2FCVE-2011-3402?kagi_q=CVE-2011-3402+details+exploitation+threat+actor+ransomware. This grants the attacker full control over the system, including the ability to install programs, modify or delete data, and create new accounts with administrative rights?query=Exploit:Win32/CVE&page=6?kagi_q=CVE-2011-3402+details+exploitation+threat+actor+ransomware.

Exploitation and Threat Actor Usage

• Active Exploitation: The vulnerability was famously exploited in the wild in November 2011 as a zero-day by the Duqu threat actor?id=CVE-2011-3402?kagi_q=CVE-2011-3402+details+exploitation+threat+actor+ransomware ^[4].
• Attack Method: Exploitation is triggered by processing specially crafted font data. This can be delivered remotely via malicious web pages or embedded within documents (such as Microsoft Word files) that the user is induced to open?id=CVE-2011-3402?kagi_q=CVE-2011-3402+details+exploitation+threat+actor+ransomware ^[2].
• User Interaction: The attack typically requires user interaction, such as visiting a compromised website or opening a malicious document?id=CVE-2011-3402?kagi_q=CVE-2011-3402+details+exploitation+threat+actor+ransomware.
• Evolution: Following its initial use by the sophisticated Duqu actor, the exploit code (and the specific font file used) was later incorporated into various crimeware exploit kits to target a wider population ^[1].

Ransomware and Proof-of-Concept

• Ransomware: While the exploit was used by advanced persistent threat (APT) actors and later by general crimeware kits, it is not primarily categorized as a "ransomware" vulnerability, though it could theoretically be used as an initial access or privilege escalation vector for any malware, including ransomware.
• Availability: Proof-of-concept exploits and the malicious font files have been publicly analyzed and are available in security research contexts ^{[1] [5]}.

Affected Products and Mitigation

• Affected Versions: The vulnerability affected a wide range of older Windows operating systems, including Windows XP (SP2/SP3), Windows Server 2003 (SP2), Windows Vista (SP2), Windows Server 2008 (SP2, R2, R2 SP1), and Windows 7 (Gold and SP1) ^[3].
• Status: Microsoft addressed this vulnerability in 2011. Systems running these legacy versions of Windows should be fully patched or, more appropriately, upgraded to modern, supported operating systems, as these versions are long past their end-of-life support dates.