CVE-2018-4987 in Acrobat Reader
Summary
by MITRE
Adobe Acrobat and Reader versions 2018.011.20038 and earlier, 2017.011.30079 and earlier, and 2015.006.30417 and earlier have an Untrusted pointer dereference vulnerability. Successful exploitation could lead to arbitrary code execution in the context of the current user.
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Analysis
by VulDB Data Team • 07/22/2024
The vulnerability identified as CVE-2018-4987 represents a critical untrusted pointer dereference flaw affecting multiple versions of Adobe Acrobat and Reader software. This security weakness resides within the document processing components that handle various file formats, particularly those involving pointer manipulation during object parsing. The vulnerability manifests when the application processes maliciously crafted PDF files that contain crafted pointer references which are not properly validated before dereferencing. Such pointer manipulation can occur during the parsing of complex document structures including embedded objects, annotations, or graphics elements that utilize dynamic memory allocation patterns.
The technical nature of this vulnerability aligns with CWE-476, which specifically addresses NULL pointer dereference conditions, though the scope extends beyond simple NULL references to encompass any untrusted pointer that may point to invalid memory locations. When exploited, the vulnerability allows attackers to manipulate memory pointers in a way that causes the application to access unauthorized memory regions. This typically occurs through carefully constructed input data that triggers the application to follow a pointer to a location that either does not exist or contains data that can be manipulated by the attacker. The flaw essentially creates a situation where the application's memory management becomes compromised, leading to potential code execution.
The operational impact of this vulnerability is severe as it enables remote code execution with the privileges of the currently logged-in user. Attackers can craft malicious PDF documents that, when opened by an affected version of Adobe Reader or Acrobat, will trigger the exploitable condition. This means that successful exploitation could result in complete system compromise without requiring any special privileges or user interaction beyond opening the malicious file. The vulnerability affects a wide range of Adobe software versions, making it particularly dangerous as it impacts multiple product lines and update cycles. The attack surface is broad since PDF files are commonly shared through email attachments, web downloads, and document sharing platforms, providing numerous potential attack vectors.
Security mitigations for CVE-2018-4987 should focus on immediate software updates and patches provided by Adobe to address the specific pointer validation issues. Organizations should implement strict PDF file scanning and validation processes before opening documents, particularly those received from untrusted sources. Network-based security controls such as web application firewalls and content filtering systems can help prevent malicious PDF files from reaching end users. Additionally, users should be educated about the risks of opening PDF files from unknown or untrusted sources, and system administrators should consider implementing sandboxing mechanisms for PDF processing. The vulnerability demonstrates the importance of proper input validation and memory management practices in software development, aligning with ATT&CK technique T1203 which covers legitimate programs and system tools used for exploitation. Organizations should also maintain current threat intelligence feeds to monitor for exploit kits or malware campaigns leveraging this specific vulnerability.