CVE-2015-6696 in Acrobat Reader
Summary
by MITRE
Heap-based buffer overflow in Adobe Reader and Acrobat 10.x before 10.1.16 and 11.x before 11.0.13, Acrobat and Acrobat Reader DC Classic before 2015.006.30094, and Acrobat and Acrobat Reader DC Continuous before 2015.009.20069 on Windows and OS X allows attackers to execute arbitrary code via unspecified vectors, a different vulnerability than CVE-2015-6698.
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Analysis
by VulDB Data Team • 06/21/2022
This heap-based buffer overflow vulnerability exists in Adobe Reader and Acrobat software versions prior to specific patched releases, representing a critical security flaw that enables remote code execution. The vulnerability affects multiple product lines including Adobe Reader 10.x before 10.1.16 and 11.x before 11.0.13, along with various Acrobat and Acrobat Reader DC Classic and Continuous versions. The flaw manifests in the heap memory management during processing of specific input data, creating conditions where attackers can manipulate memory layout to execute arbitrary code. This vulnerability operates through unspecified vectors that differ from CVE-2015-6698, indicating a distinct attack surface within the software's memory handling mechanisms. The security impact is severe as it allows attackers to gain full control over affected systems, making it a prime target for exploitation in advanced persistent threat campaigns.
The technical implementation of this buffer overflow occurs within Adobe's PDF processing engine where insufficient bounds checking allows data to be written beyond allocated heap memory regions. When the vulnerable software processes maliciously crafted PDF files or embedded content, the heap corruption creates opportunities for attackers to overwrite critical memory structures including function pointers or return addresses. This memory corruption can be leveraged to redirect program execution flow to attacker-controlled code, bypassing modern security mitigations such as DEP and ASLR. The vulnerability's classification as heap-based indicates that the overflow specifically targets heap memory allocation patterns rather than stack-based buffers, making it particularly challenging to detect and exploit due to the dynamic nature of heap memory management. The exploitability is enhanced by the fact that these applications are commonly used for opening PDF documents, making the attack surface broad and accessible through various delivery mechanisms including email attachments, web downloads, and malicious websites.
The operational impact of this vulnerability extends beyond simple code execution to encompass complete system compromise and potential lateral movement within network environments. Attackers can leverage this vulnerability to establish persistent access, escalate privileges, and deploy additional malware payloads. The vulnerability affects both Windows and OS X operating systems, demonstrating the cross-platform nature of Adobe's security issues and the widespread potential for exploitation across different computing environments. Organizations utilizing these affected versions face significant risk of data breaches, system infiltration, and operational disruption. The vulnerability's presence in Acrobat Reader DC Classic and Continuous versions indicates that even newer product lines were not immune to similar memory corruption issues, highlighting the complexity of maintaining security in complex software ecosystems. Security researchers have identified this as a critical threat requiring immediate remediation due to its potential for automated exploitation and the difficulty in detecting such attacks in network traffic.
Mitigation strategies for this vulnerability primarily involve immediate patching of affected software versions to the latest releases containing security fixes. Organizations should implement comprehensive software inventory management to identify all instances of vulnerable Adobe products across their networks. Network segmentation and application whitelisting can provide additional defense-in-depth measures to prevent exploitation attempts. Regular security awareness training for users helps reduce the risk of social engineering attacks that might deliver malicious PDF content. System monitoring should focus on detecting unusual memory allocation patterns and potential exploitation attempts through endpoint detection and response solutions. The vulnerability aligns with attack patterns described in the attack tree methodology where memory corruption exploits are classified as high-value targets for adversaries. Security teams should also consider implementing sandboxing mechanisms for PDF processing to isolate potentially malicious content from core system resources. Compliance with industry standards such as those outlined in the CWE catalog for buffer overflow vulnerabilities (cwe-121) and the MITRE ATT&CK framework's techniques for code injection and privilege escalation provides structured approaches for defending against this class of threats.