CVE-2019-7771 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 an out-of-bounds read vulnerability. Successful exploitation could lead to information disclosure.
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Analysis
by VulDB Data Team • 06/14/2024
Adobe Acrobat and Reader applications contain a critical out-of-bounds read vulnerability that affects multiple version ranges across different release cycles. This vulnerability stems from improper input validation within the document parsing mechanisms that process pdf files. The flaw manifests when the application attempts to read memory locations beyond the allocated buffer boundaries while processing malformed pdf content. The vulnerability is categorized under CWE-125 as an out-of-bounds read condition, which represents a fundamental memory safety issue that can be exploited to access sensitive data from adjacent memory regions. The affected versions include 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, indicating this issue spans multiple major releases and represents a persistent security gap in the software's memory management.
The exploitation of this vulnerability follows a well-established attack pattern that aligns with techniques described in the attack tree framework under the MITRE ATT&CK methodology for privilege escalation and information gathering. An attacker can craft a malicious pdf document that triggers the out-of-bounds read condition when the vulnerable application attempts to parse specific file structures. This particular vulnerability does not require user interaction beyond opening the malicious file, making it particularly dangerous in phishing campaigns or targeted attacks. When the application encounters malformed data structures in the pdf file, it attempts to access memory locations that are not properly validated, potentially exposing sensitive information stored in adjacent memory segments. The information disclosure aspect of this vulnerability can include system memory contents, application state data, or potentially even user credentials if they happen to be stored in accessible memory regions.
The operational impact of this vulnerability extends beyond simple information disclosure to potentially enable more sophisticated attacks within the targeted environment. The ability to read arbitrary memory locations provides attackers with potential access to sensitive data such as encryption keys, authentication tokens, or other confidential information that may be stored in the application's memory space. This vulnerability can be particularly dangerous in enterprise environments where pdf documents are frequently exchanged and processed, as it can serve as a stepping stone for further exploitation attempts. The vulnerability's presence across multiple version lines indicates that organizations using older releases of Adobe Acrobat and Reader are at risk, regardless of their specific version, making it a widespread concern that affects many users and organizations. The out-of-bounds read condition can also potentially cause application instability or crashes, leading to denial of service conditions that may impact productivity.
Organizations should implement immediate mitigation strategies including prompt patching of all affected Adobe Acrobat and Reader installations to the latest available versions that address this vulnerability. The recommended remediation approach aligns with standard vulnerability management practices and security hardening procedures. Additional protective measures include implementing pdf file scanning and validation mechanisms, restricting user permissions when processing pdf documents, and employing network-based security controls such as web application firewalls or content filtering solutions. Security teams should also consider implementing monitoring for suspicious pdf file processing activities and conducting regular vulnerability assessments to identify other potential security gaps in their document processing workflows. The vulnerability's classification under CWE-125 emphasizes the need for proper input validation and memory boundary checking in all software applications, particularly those handling untrusted input data. Organizations should also consider implementing sandboxing techniques for pdf processing and establishing incident response procedures specifically designed to handle potential exploitation of memory safety vulnerabilities in document processing applications.