CVE-2024-20734 in Acrobat 2020
Summary
by MITRE • 02/15/2024
Acrobat Reader versions 20.005.30539, 23.008.20470 and earlier are affected by a Use After Free vulnerability that could lead to disclosure of sensitive memory. An attacker could leverage this vulnerability to bypass mitigations such as ASLR. Exploitation of this issue requires user interaction in that a victim must open a malicious file.
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Analysis
by VulDB Data Team • 07/05/2026
This vulnerability represents a critical use after free condition in Adobe Acrobat Reader affecting multiple version ranges including 20.005.30539 and 23.008.20470 along with earlier releases. The flaw occurs when the application improperly handles memory management during processing of specific file formats, creating opportunities for memory corruption that can be exploited by malicious actors. The vulnerability is classified as a use after free issue which falls under CWE-416, representing an improper handling of memory allocation and deallocation patterns where freed memory is accessed beyond its intended lifecycle. Such memory management errors create exploitable conditions that can allow attackers to manipulate application behavior through carefully crafted file inputs.
The security implications extend beyond simple memory corruption as this vulnerability specifically enables bypassing critical operating system mitigations such as Address Space Layout Randomization which is designed to prevent exploitation by randomizing memory layout addresses. When an attacker successfully exploits this use after free condition, they can gain access to sensitive memory regions that contain information about the application's internal state and memory layout, effectively undermining fundamental security protections that modern systems rely upon. The attack vector requires user interaction through opening a malicious file which aligns with typical phishing or social engineering attack patterns commonly observed in exploit campaigns targeting document readers.
The operational impact of this vulnerability creates significant risk for organizations relying on Acrobat Reader for document processing, as it enables potential remote code execution capabilities when combined with other exploitation techniques. Attackers can leverage the memory disclosure to gather information about process memory structures and potentially identify offsets for more sophisticated attacks including stack or heap spraying techniques. This vulnerability represents a classic example of how memory safety issues in widely deployed software can create persistent security risks that remain exploitable across multiple versions and deployment scenarios.
Organizations should prioritize immediate patching of affected Acrobat Reader installations to mitigate this vulnerability, as the use after free condition provides attackers with sufficient control over application memory to potentially execute arbitrary code. The recommended mitigation strategy includes implementing strict file validation procedures and deploying endpoint protection solutions that can detect and prevent execution of malicious documents. Additionally, security teams should consider implementing network segmentation controls to limit potential lateral movement if exploitation occurs, while maintaining regular vulnerability assessments to identify similar memory management issues in other applications within the organization's attack surface. This vulnerability demonstrates the ongoing importance of robust memory safety practices in software development and highlights how seemingly simple memory management errors can create significant security implications in widely used applications.