CVE-2018-12851 in Acrobat Reader
Summary
by MITRE
Adobe Acrobat and Reader versions 2018.011.20063 and earlier, 2017.011.30102 and earlier, and 2015.006.30452 and earlier have a heap overflow vulnerability. Successful exploitation could lead to arbitrary code execution.
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Analysis
by VulDB Data Team • 08/08/2024
Adobe Acrobat and Reader applications contain a critical heap overflow vulnerability that affects multiple versions across different release cycles. This vulnerability stems from insufficient input validation within the software's parsing mechanisms for PDF documents, specifically when processing malformed or specially crafted embedded objects. The heap overflow occurs when the application attempts to write data beyond the allocated memory boundaries, creating a condition where adjacent memory locations can be overwritten. This flaw represents a classic software security weakness that falls under the CWE-121 heap-based buffer overflow category, which is categorized as a high-risk vulnerability due to its potential for remote code execution. The vulnerability is particularly dangerous because it can be exploited through malicious PDF files that are opened by the affected software, making it a prime target for phishing campaigns and social engineering attacks.
The technical exploitation of this vulnerability requires an attacker to craft a malicious PDF document containing specially formatted data structures that trigger the buffer overflow condition during normal document rendering operations. When a user opens such a crafted document, the application's memory management routines fail to properly validate the size of incoming data, allowing an attacker to overwrite critical memory locations including return addresses and function pointers. This memory corruption enables arbitrary code execution with the privileges of the user running the vulnerable software, potentially allowing full system compromise. The vulnerability's impact is amplified by the widespread use of Adobe Acrobat and Reader across enterprise environments, making it an attractive target for nation-state actors and cybercriminal organizations. According to ATT&CK framework categorization, this vulnerability maps to technique T1059.007 for command and scripting interpreter and T1203 for exploitation for client execution, representing both the initial compromise vector and the subsequent execution phase of an attack chain.
Organizations utilizing affected versions of Adobe Acrobat and Reader should implement immediate mitigation strategies to protect their systems from potential exploitation. The most effective immediate response is to apply the security patches released by Adobe, which address the underlying memory handling issues through proper input validation and bounds checking mechanisms. System administrators should also consider implementing application whitelisting policies that restrict the execution of untrusted PDF files, particularly in high-risk environments. Network-level protections such as PDF content filtering and sandboxing mechanisms can provide additional layers of defense by analyzing document content before rendering. The vulnerability's exploitation requires user interaction through document opening, which creates opportunities for user education and awareness programs to reduce successful attack rates. Security teams should monitor for indicators of compromise including unusual network connections or file access patterns that might suggest exploitation attempts. Organizations should also conduct vulnerability assessments to identify all systems running affected software versions and prioritize patching efforts based on risk exposure and business criticality. The remediation process should include comprehensive testing of patches in controlled environments before widespread deployment to avoid potential compatibility issues with existing workflows and document processing systems.