CVE-2016-6944 in Acrobat Reader
Summary
by MITRE
Use-after-free vulnerability in Adobe Reader and Acrobat before 11.0.18, Acrobat and Acrobat Reader DC Classic before 15.006.30243, and Acrobat and Acrobat Reader DC Continuous before 15.020.20039 on Windows and OS X allows attackers to execute arbitrary code via unspecified vectors, a different vulnerability than CVE-2016-1089, CVE-2016-1091, CVE-2016-6945, CVE-2016-6946, CVE-2016-6949, CVE-2016-6952, CVE-2016-6953, CVE-2016-6961, CVE-2016-6962, CVE-2016-6963, CVE-2016-6964, CVE-2016-6965, CVE-2016-6967, CVE-2016-6968, CVE-2016-6969, CVE-2016-6971, CVE-2016-6979, CVE-2016-6988, and CVE-2016-6993.
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Analysis
by VulDB Data Team • 09/23/2022
The CVE-2016-6944 vulnerability represents a critical use-after-free flaw affecting Adobe Reader and Acrobat products across multiple versions and operating systems. This vulnerability specifically impacts Adobe Reader versions before 11.0.18, Acrobat versions before 11.0.18, and various Acrobat Reader DC Classic and Continuous versions before their respective patches. The flaw manifests in the way these applications handle memory management when processing certain file formats, creating a scenario where freed memory blocks can be accessed and potentially exploited by malicious actors.
This use-after-free vulnerability falls under the CWE-416 category, which specifically addresses the use of freed memory conditions that can lead to arbitrary code execution. The technical nature of this flaw involves the application's failure to properly manage object references within its memory heap, allowing attackers to manipulate freed memory locations and inject malicious code. The vulnerability operates through unspecified vectors that typically involve crafted PDF files or other document formats that trigger the problematic code path within the Adobe application's parser.
The operational impact of CVE-2016-6944 is severe and far-reaching, as it provides attackers with a pathway to achieve remote code execution on vulnerable systems. When an attacker successfully exploits this vulnerability, they can execute arbitrary code with the privileges of the affected application, typically resulting in complete system compromise. The attack surface is particularly broad given that Adobe Reader and Acrobat are widely deployed across enterprise environments, making this vulnerability attractive to threat actors seeking persistent access to target networks. The vulnerability's presence in both Windows and OS X operating systems further expands its potential impact.
Mitigation strategies for CVE-2016-6944 primarily focus on immediate patch application and operational security measures. Organizations should prioritize updating to the patched versions of Adobe Reader and Acrobat, specifically targeting the versions mentioned in the advisory. Additionally, implementing security controls such as Adobe's Enhanced Security Configuration, which restricts file access and limits application capabilities, can significantly reduce exploitation risk. Network-based mitigations including sandboxing PDF processing and implementing strict email filtering can provide additional protection layers. The ATT&CK framework categorizes this vulnerability under the T1059 technique for command and scripting interpreter, as exploitation typically results in code execution that can be leveraged for further attack progression. Security teams should also consider implementing monitoring for suspicious PDF file handling activities and establish incident response procedures specifically addressing potential exploitation of use-after-free vulnerabilities in document processing applications.