CVE-2016-1111 in Acrobat Reader
Summary
by MITRE
Double free vulnerability in Adobe Reader and Acrobat before 11.0.14, Acrobat and Acrobat Reader DC Classic before 15.006.30119, and Acrobat and Acrobat Reader DC Continuous before 15.010.20056 on Windows and OS X allows attackers to execute arbitrary code via a crafted Graphics State dictionary.
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Analysis
by VulDB Data Team • 07/28/2022
This vulnerability represents a critical double free condition in Adobe Reader and Acrobat software versions prior to specific patches, creating a remote code execution risk that aligns with CWE-415. The flaw exists within the handling of Graphics State dictionaries in PDF documents, where improper memory management leads to the same memory block being freed twice during processing. Attackers can exploit this by crafting malicious PDF files containing specially constructed Graphics State dictionaries that trigger the vulnerable code path in the software's PDF parsing engine.
The technical implementation of this vulnerability leverages the memory corruption inherent in the double free scenario, where the heap management system encounters a situation where a memory chunk is deallocated twice, potentially allowing attackers to manipulate the heap layout and control program execution flow. This type of vulnerability falls under the ATT&CK technique T1059.007 for Command and Scripting Interpreter and T1566 for Phishing with Malicious Attachments, as it enables attackers to deliver malicious payloads through PDF documents that appear legitimate. The vulnerability affects both Windows and macOS operating systems, demonstrating the cross-platform nature of the memory management flaw.
The operational impact of this vulnerability extends beyond simple code execution, as it allows attackers to gain complete control over the affected system. When exploited, the double free condition can be leveraged to overwrite critical memory structures, potentially enabling privilege escalation or persistent backdoor installation. The vulnerability's exploitation requires minimal user interaction beyond opening a malicious PDF document, making it particularly dangerous in targeted attack scenarios. Organizations running unpatched versions of Adobe Reader and Acrobat face significant risk of compromise, as the vulnerability can be exploited through various attack vectors including email attachments, web downloads, and malicious websites.
Mitigation strategies should prioritize immediate patching of all affected Adobe products to the latest versions, as Adobe released security updates addressing this specific vulnerability. System administrators should implement strict PDF file filtering and sandboxing mechanisms to reduce the attack surface, particularly in environments where users may encounter untrusted PDF content. Network-based protections should include deep packet inspection for suspicious PDF file characteristics and implementation of email filtering solutions that can identify and quarantine potentially malicious attachments. The vulnerability highlights the importance of maintaining up-to-date software patches and implementing defense-in-depth strategies that limit the impact of such memory corruption vulnerabilities. Additionally, user education programs should emphasize the dangers of opening PDF files from untrusted sources, as social engineering remains a critical factor in successful exploitation of such vulnerabilities.