CVE-2018-12761 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 • 08/12/2024
Adobe Acrobat and Reader applications contain a critical out-of-bounds read vulnerability that affects multiple versions across different release cycles. This vulnerability resides in the handling of malformed PDF files and represents a fundamental memory access flaw that can be exploited by malicious actors. The issue manifests when the software processes certain PDF objects without proper bounds checking, allowing an attacker to read memory locations beyond the intended buffer boundaries. This particular vulnerability has been classified under CWE-129 as an insufficient bounds checking mechanism, which directly relates to the core problem of improper input validation. The vulnerability affects Adobe Acrobat and Reader versions 2018.011.20040 and earlier, 2017.011.30080 and earlier, and 2015.006.30418 and earlier, indicating a widespread issue across multiple major release lines. The operational impact of this vulnerability extends beyond simple information disclosure, as it can potentially expose sensitive memory contents including encryption keys, user credentials, or other confidential data that may be stored in adjacent memory locations. According to ATT&CK framework category T1059, this vulnerability could enable adversaries to gain unauthorized access to system resources through the exploitation of application-level flaws. The out-of-bounds read condition creates a pathway for attackers to potentially extract information from memory segments that should remain protected, making it particularly dangerous in environments where sensitive documents are processed. When exploited successfully, this vulnerability allows an attacker to craft specially malformed PDF files that trigger the memory access error, leading to the disclosure of information that could be used for further exploitation or reconnaissance activities. The vulnerability's impact is amplified by the widespread use of Adobe Reader across enterprise and consumer environments, making it an attractive target for threat actors seeking to gain access to sensitive information. Security researchers have identified that the flaw occurs during the parsing of PDF objects where the application fails to validate the size or structure of data before attempting to read from memory locations. This type of vulnerability is particularly concerning because it can be triggered through simple document opening, requiring minimal user interaction beyond opening the malicious file. The information disclosure aspect of this vulnerability could expose system state information, application memory contents, or other sensitive data that may be accessible through the memory read operations. Organizations should prioritize patching affected versions as this vulnerability represents a significant risk to data confidentiality and system integrity. The remediation strategy involves updating to patched versions of Adobe Acrobat and Reader where proper bounds checking has been implemented to prevent the out-of-bounds memory access. Additionally, implementing security controls such as PDF content filtering, sandboxing mechanisms, and network-based protections can help mitigate the risk while waiting for patches to be deployed across all affected systems. The vulnerability demonstrates the importance of proper input validation and memory management practices in software development, aligning with security best practices outlined in industry standards for preventing memory corruption vulnerabilities.