CVE-2018-5062 in Acrobat Reader
Summary
by MITRE
Adobe Acrobat and Reader 2018.011.20040 and earlier, 2017.011.30080 and earlier, and 2015.006.30418 and earlier versions have an Out-of-bounds read vulnerability. Successful exploitation could lead to information disclosure.
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Analysis
by VulDB Data Team • 08/11/2024
Adobe Acrobat and Reader applications contain a critical out-of-bounds read vulnerability that affects multiple version ranges including 2018.011.20040 and earlier, 2017.011.30080 and earlier, and 2015.006.30418 and earlier. This vulnerability resides in the handling of malformed PDF files and represents a classic memory safety issue that falls under the Common Weakness Enumeration category CWE-125. The flaw occurs when the software processes certain PDF objects without proper bounds checking, allowing an attacker to craft malicious documents that trigger memory access violations. When exploited, this vulnerability enables an attacker to read data from memory locations that should not be accessible, potentially exposing sensitive information such as stack contents, heap data, or other application memory segments. The vulnerability is particularly concerning because it can be triggered through simple document manipulation and does not require any special privileges or user interaction beyond opening the malicious file. According to the ATT&CK framework, this represents a technique categorized under privilege escalation and information gathering, as attackers can leverage the out-of-bounds read to extract confidential data from the target system. The operational impact extends beyond simple information disclosure, as the extracted memory contents may contain cryptographic keys, user credentials, or other sensitive application data. The vulnerability demonstrates a fundamental flaw in input validation and memory management within the PDF processing engine, highlighting the importance of proper bounds checking in handling untrusted data. Attackers can exploit this by crafting PDF files that contain malformed data structures designed to trigger the memory access violation, potentially leading to full system compromise. Organizations should prioritize patching affected versions and implementing additional security controls such as sandboxing PDF processing, network segmentation, and monitoring for suspicious document handling activities.
This vulnerability specifically affects the parsing functionality of Adobe's PDF engine where buffer boundaries are not properly validated during object processing. The out-of-bounds read occurs when the application attempts to access memory locations beyond the allocated buffer space, typically triggered by malformed PDF streams or arrays. The technical implementation involves the software's failure to validate array indices or string lengths before accessing memory locations, creating opportunities for attackers to manipulate memory contents. The attack surface is broad since PDF documents are commonly shared across networks and email systems, making this vulnerability particularly dangerous in enterprise environments. Security researchers have noted that such vulnerabilities often serve as initial access vectors for more sophisticated attacks, as the extracted information can be used to develop additional exploitation techniques or to identify system weaknesses. The vulnerability's classification as an information disclosure issue aligns with ATT&CK technique T1005, where adversaries gather data from the local system. Organizations should implement comprehensive patch management programs to address this vulnerability, as Adobe released security updates specifically targeting this issue. Additional defensive measures include deploying email filtering solutions that can detect and block malicious PDF attachments, implementing application whitelisting policies to restrict PDF processing to trusted applications, and conducting regular security assessments to identify systems running vulnerable versions. The vulnerability also underscores the need for robust input validation mechanisms and the implementation of modern memory safety practices such as address space layout randomization and stack canaries to mitigate the impact of similar future vulnerabilities.