CVE-2018-4957 in Acrobat Reader
Summary
by MITRE
Adobe Acrobat and Reader versions 2018.011.20038 and earlier, 2017.011.30079 and earlier, and 2015.006.30417 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 • 07/21/2024
Adobe Acrobat and Reader applications contain a critical out-of-bounds read vulnerability that affects multiple version ranges including 2018.011.20038 and earlier, 2017.011.30079 and earlier, and 2015.006.30417 and earlier. This vulnerability resides in the handling of PDF documents and occurs when the software processes malformed or specially crafted PDF files. The flaw manifests as an improper bounds checking mechanism within the parsing logic that fails to validate array indices or memory access boundaries before reading data from memory locations. When an attacker crafts a malicious PDF file containing malformed data structures, the application attempts to read memory beyond the allocated buffer boundaries, resulting in an out-of-bounds read condition that can expose sensitive information stored in adjacent memory locations.
The technical nature of this vulnerability aligns with CWE-129, which describes improper validation of array index bounds, and represents a classic example of memory safety issues that have been extensively documented in the cybersecurity community. This type of vulnerability falls under the ATT&CK technique T1059.007 for Command and Scripting Interpreter and T1557 for Adversarial Process Injection, as attackers can potentially leverage such flaws to extract confidential data or manipulate application behavior. The operational impact of this vulnerability extends beyond simple information disclosure, as the leaked memory contents may contain cryptographic keys, user credentials, session tokens, or other sensitive data that could be exploited in subsequent attacks. Attackers could potentially use this vulnerability to gain unauthorized access to protected documents or system resources, making it particularly dangerous in enterprise environments where Acrobat Reader is widely deployed.
The exploitation of this vulnerability requires the victim to open a maliciously crafted PDF file, typically through social engineering techniques such as phishing emails or compromised websites. The attack vector represents a common delivery method in targeted campaigns where adversaries use the widespread adoption of PDF readers to their advantage. Organizations should implement multiple layers of defense including regular patch management, email filtering solutions, web application firewalls, and user education programs to mitigate the risk. Security teams should also monitor for suspicious PDF file activity and consider implementing sandboxing solutions for PDF processing. The vulnerability underscores the importance of maintaining up-to-date software versions and following secure coding practices that emphasize bounds checking and memory safety validation. Organizations using affected versions should urgently apply the vendor patches released in response to this vulnerability and conduct security assessments to identify any potential exploitation attempts that may have occurred prior to patch deployment.