CVE-2011-2105 in Acrobat
Summary
by MITRE
Adobe Reader and Acrobat 8.x before 8.3, 9.x before 9.4.5, and 10.x before 10.1 on Windows and Mac OS X allow attackers to cause a denial of service (memory corruption) or possibly have unspecified other impact via crafted font data.
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Analysis
by VulDB Data Team • 12/08/2024
Adobe Reader and Acrobat versions 8.x before 8.3, 9.x before 9.4.5, and 10.x before 10.1 contain a critical memory corruption vulnerability that arises from improper handling of crafted font data within the application's font processing subsystem. This vulnerability falls under the CWE-125 vulnerability type, which represents an out-of-bounds read condition that can lead to memory corruption and potentially arbitrary code execution. The flaw exists in how these applications parse and render font files, particularly when encountering malformed or specially crafted font data that exceeds expected memory boundaries during processing.
The technical implementation of this vulnerability occurs within the font rendering engine of Adobe Reader and Acrobat, where insufficient input validation and memory boundary checks allow maliciously constructed font files to trigger buffer overflows or memory corruption conditions. When the vulnerable application attempts to process the crafted font data, it fails to properly validate the font structure and memory allocation, leading to unpredictable behavior that can manifest as application crashes, memory corruption, or potentially more severe consequences. The vulnerability is particularly dangerous because it can be exploited through various font formats including but not limited to TrueType and OpenType fonts that are commonly embedded in pdf documents.
From an operational perspective, this vulnerability presents significant risk to organizations that rely heavily on Adobe Reader for document processing, as attackers can leverage this weakness to cause denial of service attacks against end-user systems or potentially execute malicious code with the privileges of the affected application. The attack vector typically involves tricking users into opening a malicious pdf document containing crafted font data, which then triggers the vulnerability during normal document rendering operations. This makes the vulnerability particularly dangerous in enterprise environments where users frequently open pdf documents from external sources without proper security screening.
The impact of this vulnerability extends beyond simple denial of service scenarios, as memory corruption issues can potentially be leveraged for privilege escalation or arbitrary code execution depending on the execution context and system configuration. Security researchers have noted that this vulnerability aligns with ATT&CK technique T1203, which involves exploiting software vulnerabilities to gain system access, and T1059, which covers command and script injection through compromised applications. Organizations should consider implementing multiple layers of defense including regular patch management, email filtering to prevent malicious pdf attachments, and user awareness training to minimize exposure to this type of attack. The vulnerability also highlights the importance of proper software input validation and memory safety practices in document processing applications, particularly those handling complex binary formats like font files.