CVE-2019-7785 in Acrobat Reader
Summary
by MITRE
Adobe Acrobat and Reader versions 2019.010.20100 and earlier, 2019.010.20099 and earlier, 2017.011.30140 and earlier, 2017.011.30138 and earlier, 2015.006.30495 and earlier, and 2015.006.30493 and earlier have a use after free vulnerability. Successful exploitation could lead to arbitrary code execution.
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Analysis
by VulDB Data Team • 06/16/2024
Adobe Acrobat and Reader contain a critical use after free vulnerability identified as CVE-2019-7785 that affects multiple product versions across different release cycles. This vulnerability resides in the handling of PDF objects within the software's processing pipeline, specifically when dealing with memory management during object destruction and subsequent reuse. The flaw manifests when the application allocates memory for certain PDF objects and then frees that memory while still maintaining pointers to the freed location, creating a scenario where subsequent operations may write data to already released memory regions. This use after free condition represents a fundamental memory safety issue that aligns with CWE-416, which specifically addresses the use of freed memory in software applications. The vulnerability is particularly concerning because it can be triggered through maliciously crafted PDF files that are opened within the affected Adobe products, making it an attractive target for attackers seeking to exploit user interactions with PDF documents.
The operational impact of CVE-2019-7785 extends beyond simple privilege escalation or denial of service scenarios, as successful exploitation can result in arbitrary code execution on the target system. Attackers can leverage this vulnerability to execute malicious payloads with the privileges of the user running the affected Adobe application, potentially leading to complete system compromise. The vulnerability's exploitation requires a user to open a specially crafted malicious PDF file, making it particularly dangerous in targeted attack scenarios where social engineering plays a significant role. This attack vector aligns with ATT&CK technique T1204.002, which describes the use of malicious files to execute code. The memory corruption aspect of this vulnerability makes it particularly challenging to detect and prevent through traditional signature-based methods, as the exploitation often occurs through legitimate application functionality that is commonly used in business environments.
Mitigation strategies for CVE-2019-7785 should prioritize immediate patch management, as Adobe has released updates addressing this specific vulnerability in their software releases. Organizations should implement a comprehensive vulnerability management program that includes regular security updates and patches for all Adobe products, particularly focusing on the affected versions mentioned in the CVE description. Network segmentation and application whitelisting can serve as additional defensive measures to limit the potential impact of exploitation attempts, while monitoring for unusual PDF file processing activities can help detect potential exploitation attempts. Security teams should also consider implementing sandboxing solutions for PDF processing and establishing strict controls around PDF file handling in enterprise environments. The vulnerability's nature as a memory corruption issue makes it particularly susceptible to exploitation through techniques such as heap spraying or return-oriented programming, which further emphasizes the need for robust exploit prevention mechanisms including address space layout randomization and data execution prevention features. Organizations should also conduct regular security awareness training to help users recognize potentially malicious PDF files and understand the risks associated with opening untrusted documents.