CVE-2018-5020 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 write 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 • 08/10/2024
The vulnerability identified as CVE-2018-5020 represents a critical out-of-bounds write flaw affecting multiple versions of Adobe Acrobat and Reader software. This vulnerability falls under the Common Weakness Enumeration category CWE-787, which specifically addresses out-of-bounds write conditions that can occur when a program attempts to write data beyond the boundaries of a fixed-length buffer. The affected versions include Adobe Acrobat and Reader 2018.011.20040 and earlier, 2017.011.30080 and earlier, and 2015.006.30418 and earlier, indicating a widespread issue across several major release cycles of the software.
The technical nature of this vulnerability stems from improper input validation within the parsing mechanisms of Adobe's document processing libraries. When the software encounters specially crafted malicious PDF files, the buffer overflow condition occurs during the processing of specific document elements, particularly those related to embedded objects or complex formatting structures. The out-of-bounds write vulnerability allows an attacker to overwrite adjacent memory locations, potentially corrupting critical program data or execution pointers. This flaw operates at the intersection of multiple attack techniques documented in the MITRE ATT&CK framework under the T1059 category for command and scripting interpreters, as successful exploitation could enable arbitrary code execution.
The operational impact of CVE-2018-5020 extends beyond simple privilege escalation, as it provides attackers with a pathway to achieve full system compromise through the execution of arbitrary code within the context of the currently logged-in user. This means that successful exploitation could result in unauthorized access to sensitive data, system reconnaissance, and potential lateral movement within a network environment. The vulnerability's exploitation requires user interaction, typically through the opening of a maliciously crafted PDF file, making it particularly dangerous in targeted phishing campaigns or supply chain attacks where social engineering elements can be combined with the technical exploit. Organizations utilizing Adobe Acrobat and Reader products across their enterprise networks face significant risk exposure, as these applications are commonly used for document sharing and business-critical workflows.
Organizations should implement immediate mitigations including prompt application of Adobe's security patches released in response to this vulnerability, which typically address the underlying buffer management issues through proper bounds checking and memory allocation procedures. Network segmentation and email filtering measures should be enhanced to prevent delivery of potentially malicious PDF attachments, while user education programs can help reduce successful exploitation attempts through awareness of suspicious file attachments. The vulnerability's classification as a remote code execution flaw necessitates comprehensive monitoring of network traffic for suspicious PDF file transfers and system logs for potential exploitation indicators. Additionally, implementing application whitelisting policies that restrict execution of untrusted PDF files in enterprise environments can provide additional defense-in-depth layers against potential exploitation attempts.