CVE-2016-2209 in Endpoint Protection
Summary
by MITRE
Buffer overflow in Dec2SS.dll in the AntiVirus Decomposer engine in Symantec Advanced Threat Protection (ATP); Symantec Data Center Security:Server (SDCS:S) 6.x through 6.6 MP1; Symantec Web Gateway; Symantec Endpoint Protection (SEP) before 12.1 RU6 MP5; Symantec Endpoint Protection (SEP) for Mac; Symantec Endpoint Protection (SEP) for Linux before 12.1 RU6 MP5; Symantec Protection Engine (SPE) before 7.0.5 HF01, 7.5.x before 7.5.3 HF03, 7.5.4 before HF01, and 7.8.0 before HF01; Symantec Protection for SharePoint Servers (SPSS) 6.0.3 through 6.0.5 before 6.0.5 HF 1.5 and 6.0.6 before HF 1.6; Symantec Mail Security for Microsoft Exchange (SMSMSE) before 7.0_3966002 HF1.1 and 7.5.x before 7.5_3966008 VHF1.2; Symantec Mail Security for Domino (SMSDOM) before 8.0.9 HF1.1 and 8.1.x before 8.1.3 HF1.2; CSAPI before 10.0.4 HF01; Symantec Message Gateway (SMG) before 10.6.1-4; Symantec Message Gateway for Service Providers (SMG-SP) 10.5 before patch 254 and 10.6 before patch 253; Norton AntiVirus, Norton Security, Norton Internet Security, and Norton 360 before NGC 22.7; Norton Security for Mac before 13.0.2; Norton Power Eraser (NPE) before 5.1; and Norton Bootable Removal Tool (NBRT) before 2016.1 allows remote attackers to execute arbitrary code via a crafted file.
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Analysis
by VulDB Data Team • 01/06/2025
The vulnerability identified as CVE-2016-2209 represents a critical buffer overflow flaw within the Dec2SS.dll component of Symantec's AntiVirus Decomposer engine, affecting multiple security products across various platforms and versions. This vulnerability resides in the decompression functionality that processes potentially malicious files, creating an attack surface where remote adversaries can exploit the flaw through crafted malicious files. The affected products span Symantec's comprehensive security portfolio including Advanced Threat Protection, Data Center Security, Web Gateway, Endpoint Protection for Windows, Mac, and Linux platforms, as well as various protection engines and specialized security solutions for SharePoint, email servers, and messaging gateways.
The technical implementation of this buffer overflow occurs within the Dec2SS.dll library which handles the decompression of security-related files within Symantec's security infrastructure. When processing specially crafted input files, the decompression engine fails to properly validate buffer boundaries, allowing attackers to write data beyond allocated memory space. This flaw manifests as a classic stack-based buffer overflow that can be leveraged to overwrite critical memory locations including return addresses and function pointers. The vulnerability's exploitation requires remote code execution capabilities since the affected components process files received from network sources or user interactions, making it particularly dangerous in enterprise environments where security products are deployed across multiple endpoints and network infrastructure components.
The operational impact of CVE-2016-2209 extends beyond simple privilege escalation, as it provides attackers with a pathway to achieve persistent system compromise across diverse Symantec security products. Attackers can craft malicious files that, when processed by any of the affected components, trigger the buffer overflow condition and subsequently execute arbitrary code with the privileges of the compromised process. This creates a significant risk for enterprise environments where Symantec security solutions are deployed, as successful exploitation could allow attackers to bypass security controls, access sensitive data, or establish persistent backdoors. The vulnerability's presence across multiple product lines including endpoint protection, email security, and web gateway solutions amplifies the potential attack surface and makes it particularly attractive to threat actors seeking to compromise enterprise security infrastructure.
Security mitigations for CVE-2016-2209 should prioritize immediate patch deployment across all affected Symantec products, with particular attention to versions identified in the vulnerability description. Organizations must ensure comprehensive testing of patches in their environments before deployment to avoid service disruptions, as the affected components are critical to security operations. Network segmentation and monitoring should be enhanced to detect potential exploitation attempts, including monitoring for unusual file processing patterns or network connections initiated by security products. The vulnerability aligns with ATT&CK technique T1059.007 for remote code execution and T1070.004 for bypassing security solutions, making it particularly relevant for organizations implementing threat hunting and detection capabilities. Additionally, implementing principle of least privilege for security product processes and regular security assessments of deployed Symantec components can help reduce the overall risk exposure. Organizations should also consider implementing file reputation systems and sandboxing mechanisms to detect and prevent execution of malicious files before they reach vulnerable components, as the buffer overflow can be triggered through various file types including compressed archives, executables, and document formats commonly processed by Symantec security solutions.