CVE-2016-6949 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-2016-6952, 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-2016-6949 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 prior to their respective patched releases. The flaw exists within the software's memory management mechanisms, creating a scenario where freed memory locations can be accessed and manipulated by malicious actors. Such vulnerabilities are particularly dangerous because they can lead to arbitrary code execution when exploited, making them prime targets for cybercriminals seeking to compromise user systems.
The technical nature of this use-after-free vulnerability stems from improper memory handling within Adobe's document processing libraries. When a program frees memory but continues to reference that memory location, attackers can manipulate the freed space to inject malicious code or redirect execution flow. This particular vulnerability operates through unspecified vectors, indicating that attackers can trigger the flaw through various attack surfaces within the Adobe Acrobat environment. The vulnerability's classification aligns with CWE-416, which specifically addresses use-after-free conditions in software applications. The attack surface is particularly broad as it affects both Windows and OS X platforms, suggesting the flaw exists in the core processing libraries shared across these operating systems.
The operational impact of this vulnerability extends beyond simple exploitation capabilities to encompass significant security risks for organizations and individual users. Successful exploitation of CVE-2016-6949 could enable attackers to execute arbitrary code with the privileges of the targeted user, potentially leading to complete system compromise. Attackers might leverage this vulnerability through malicious PDF files delivered via email phishing campaigns, compromised websites, or other social engineering vectors. The vulnerability's persistence across multiple product versions indicates a fundamental flaw in Adobe's memory management implementation that required extensive patching across different software streams. Organizations relying on Adobe Reader for document processing faced substantial risk exposure, as these applications are frequently used in enterprise environments where sensitive data is processed.
Mitigation strategies for CVE-2016-6949 should prioritize immediate patch deployment across all affected Adobe products, as this represents a critical security vulnerability requiring urgent attention. Security administrators should implement layered defenses including email filtering solutions that can detect and block malicious PDF attachments, network segmentation to limit potential attack vectors, and user education programs to reduce social engineering success rates. The vulnerability's relationship to the broader ATT&CK framework demonstrates how such memory corruption flaws can map to multiple attack techniques including privilege escalation and code injection. Regular security assessments should verify that patches have been properly deployed and that no legacy systems remain vulnerable. Organizations should also consider implementing application whitelisting policies that restrict execution of untrusted PDF files, particularly in high-security environments where the risk of exploitation is elevated.