CVE-2016-6953 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-2016-6944, CVE-2016-6945, CVE-2016-6946, CVE-2016-6949, CVE-2016-6952, 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-2016-6953 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 prior to 11.0.18, Acrobat versions before 11.0.18, and various DC Classic and Continuous versions before their respective patch releases. The flaw exists within the software's memory management mechanisms, creating a scenario where freed memory blocks can be accessed and potentially overwritten by malicious code. This particular vulnerability operates through unspecified attack vectors that distinguish it from numerous other related vulnerabilities in the same timeframe, making it particularly challenging to detect and mitigate.
The technical implementation of this use-after-free vulnerability stems from improper handling of memory objects within Adobe's PDF processing engine. When processing maliciously crafted PDF files, the application fails to properly manage object lifecycles, allowing attackers to manipulate freed memory locations. This memory corruption issue can be exploited to execute arbitrary code with the privileges of the victim user. The vulnerability's classification under CWE-416 indicates improper cleanup of memory resources, which directly enables the exploitation scenario. The attack surface extends across both Windows and OS X platforms, demonstrating the cross-platform nature of the flaw and its potential for widespread impact.
From an operational perspective, this vulnerability poses significant risks to enterprise environments and individual users alike. Attackers can craft malicious PDF documents that, when opened by vulnerable Adobe applications, trigger the memory corruption leading to remote code execution. The exploitability of this vulnerability means that simply viewing a malicious document could compromise a system, making it particularly dangerous for email attachments and web-based document delivery. The vulnerability's presence in both classic and continuous DC versions indicates that organizations using Adobe's document processing software across different deployment models face identical security risks, requiring comprehensive patch management strategies.
Security professionals should implement immediate mitigation measures including mandatory patch deployment for all affected Adobe Reader and Acrobat versions. The vulnerability's classification as a remote code execution flaw necessitates network-level protections such as email filtering and web proxy configurations to prevent access to potentially malicious PDF content. Organizations should also consider implementing application whitelisting policies to restrict execution of Adobe applications in high-risk environments. The ATT&CK framework categorizes this vulnerability under the T1059.007 technique for remote code execution through legitimate system processes, emphasizing the need for layered defensive measures. Additionally, regular security assessments and vulnerability scanning should be conducted to identify any remaining instances of vulnerable software within the enterprise infrastructure, ensuring comprehensive protection against similar memory corruption vulnerabilities.