CVE-2019-7762 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 • 06/17/2024
Adobe Acrobat and Reader contain a critical use after free vulnerability that affects multiple versions across different release cycles. This vulnerability arises from improper memory management within the software's handling of object references, creating opportunities for attackers to manipulate freed memory regions. The flaw exists in the way the applications process certain PDF objects, specifically when dealing with dynamic memory allocation and deallocation sequences that do not properly validate object lifetimes. When a memory block is freed but still referenced by subsequent operations, attackers can exploit this condition to execute arbitrary code within the context of the vulnerable application.
The technical implementation of this use after free vulnerability stems from inadequate bounds checking and memory state validation mechanisms within Adobe's PDF processing engine. Attackers can craft malicious PDF files that trigger the exploitation scenario by manipulating object references in ways that cause the application to access memory that has already been deallocated. This type of vulnerability falls under the CWE-416 category, which specifically addresses use after free conditions in memory management. The vulnerability is particularly dangerous because it allows for arbitrary code execution without requiring user interaction beyond opening the malicious document, making it a prime target for zero-day exploits in targeted attacks.
The operational impact of this vulnerability extends beyond simple privilege escalation scenarios, as successful exploitation can result in complete system compromise. Attackers leveraging this vulnerability can execute malicious code with the same privileges as the affected application, typically running with user-level permissions but potentially elevated through privilege escalation techniques. The exploitability of this vulnerability aligns with ATT&CK technique T1059.007, which covers command and scripting interpreter usage, as attackers can leverage the arbitrary code execution capability to establish persistent access or deploy additional malicious payloads. The widespread adoption of Adobe Reader across enterprise environments makes this vulnerability particularly attractive to threat actors targeting organizations for data exfiltration or lateral movement.
Mitigation strategies for this vulnerability should prioritize immediate patching of all affected versions, with particular attention to the specific release versions mentioned in the CVE. Organizations should implement network segmentation and application whitelisting policies to prevent unauthorized PDF processing, while also deploying email filtering solutions that can identify and block potentially malicious PDF attachments. Security monitoring should focus on detecting anomalous PDF processing activities, including unexpected memory access patterns or unusual network connections initiated by Adobe applications. The vulnerability's nature as a use after free condition makes it particularly challenging to detect through traditional signature-based methods, requiring behavioral analysis and heuristic approaches to identify exploitation attempts. Additionally, implementing sandboxing mechanisms for PDF processing and maintaining up-to-date threat intelligence feeds can provide additional layers of protection against exploitation attempts targeting this specific vulnerability.