CVE-2024-20749 in Acrobat 2020
Summary
by MITRE • 02/15/2024
Acrobat Reader versions 20.005.30539, 23.008.20470 and earlier are affected by an out-of-bounds read 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 • 06/18/2026
This vulnerability resides in Adobe Acrobat Reader software affecting versions up to 20.005.30539 and 23.008.20470, representing a critical out-of-bounds read flaw that fundamentally compromises memory safety mechanisms within the application. The technical implementation of this vulnerability stems from insufficient input validation during file parsing operations, specifically when processing malformed or specially crafted PDF documents that trigger memory access violations beyond allocated buffer boundaries. This particular flaw manifests as an out-of-bounds read condition that occurs when the application attempts to access memory locations that fall outside the intended data structures, creating opportunities for information disclosure and potential exploitation. The vulnerability directly maps to CWE-125, which describes out-of-bounds read conditions in software implementations, and can be leveraged to bypass critical security mitigations such as Address Space Layout Randomization that rely on maintaining memory integrity. The attack vector requires social engineering to trick victims into opening maliciously crafted PDF files, making this a user-interaction dependent exploit that aligns with ATT&CK technique T1204.201 for valid accounts and T1566 for social engineering. When successfully exploited, the vulnerability can lead to sensitive memory disclosure that may reveal stack canaries, heap metadata, or other security-relevant information that could be used to defeat additional protections like stack canaries or control flow integrity mechanisms. The operational impact extends beyond simple information disclosure as attackers can potentially reconstruct memory layouts and exploit additional vulnerabilities that may exist in the same application context. The nature of this vulnerability means that exploitation typically requires precise control over memory layout and understanding of the target system's memory organization, making it particularly dangerous in environments where multiple security layers are deployed. The memory disclosure aspect of this vulnerability specifically undermines the effectiveness of modern exploit mitigation techniques, as attackers can use the leaked information to bypass ASLR protections that randomize memory addresses, thereby enabling more reliable exploitation of subsequent vulnerabilities. Organizations should prioritize immediate patching of affected versions, as the vulnerability exists in widely deployed software and represents a significant risk to enterprise security environments where PDF documents are frequently processed. The remediation strategy should include comprehensive vulnerability assessment of all systems running affected Acrobat Reader versions, alongside implementation of additional security controls such as PDF sandboxing, content filtering, and user education programs to reduce the likelihood of successful exploitation through social engineering attacks.