CVE-2018-12846 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 version ranges including 2018.011.20063 and earlier, 2017.011.30102 and earlier, and 2015.006.30452 and earlier. This vulnerability stems from improper input validation within the PDF processing engine when handling malformed or specially crafted PDF files. The heap overflow occurs during the parsing of specific PDF objects that trigger buffer manipulation routines without adequate bounds checking. When an attacker crafts a malicious PDF document containing oversized data structures or malformed object sequences, the application fails to properly validate memory allocation boundaries, leading to memory corruption that can be exploited to execute arbitrary code. This vulnerability represents a classic heap-based buffer overflow scenario classified under CWE-121 which specifically addresses unsafe use of memory allocation functions. The technical flaw manifests when the application attempts to write data beyond the allocated heap memory boundaries, potentially overwriting adjacent memory segments including function pointers, return addresses, or other critical control structures. The operational impact of this vulnerability is severe as it provides attackers with a remote code execution vector that can be leveraged through social engineering tactics such as phishing emails containing malicious PDF attachments. Attackers can craft PDF files that, when opened by vulnerable versions of Adobe Acrobat or Reader, trigger the heap overflow condition and subsequently gain control over the victim's system. The exploitation process typically involves leveraging the heap overflow to overwrite the instruction pointer or other control flow mechanisms, allowing for code injection attacks that can execute malicious payloads with the privileges of the user running the vulnerable application. This vulnerability aligns with several techniques documented in the ATT&CK framework under the Tactic of Execution, specifically targeting legitimate programs and user processes to gain system access. Organizations using affected versions of Adobe Acrobat and Reader face significant risk exposure, as this vulnerability can be exploited without user interaction once the malicious PDF is opened, making it particularly dangerous in enterprise environments where users frequently open documents from external sources. The vulnerability's impact extends beyond individual user systems to potentially compromise entire network infrastructures, especially when attackers use the compromised systems as launch points for further lateral movement and privilege escalation attacks. Security practitioners should note that this vulnerability represents a persistent threat vector that requires immediate remediation through official Adobe security patches, as the exploitation window remains open for all affected versions. The vulnerability demonstrates the ongoing challenges in PDF processing security and highlights the importance of robust input validation and memory safety practices in commercial software applications. Organizations must implement comprehensive patch management procedures to ensure all instances of affected software are updated promptly, while also considering network segmentation and email filtering controls to reduce the likelihood of successful exploitation attempts. The vulnerability serves as a reminder of the critical need for continuous security monitoring and the importance of maintaining up-to-date security patches across all enterprise software systems to prevent exploitation of known vulnerabilities that can lead to complete system compromise.