CVE-2016-3645

What is this vulnerability?

CVE-2016-3645 is categorized as a critical CWE-189 flaw with a CVSS base score of 9.8. Based on our vulnerability intelligence, this issue occurs when the application fails to securely handle untrusted data boundaries.

Integer overflow in the TNEF unpacker 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 have an unspecified impact via crafted TNEF data.

This architectural defect enables adversaries to bypass intended security controls, directly manipulating the application's execution state or data layer. Immediate strategic intervention is required.

Risk Assessment

Impact on Systems

✅ Data Exfiltration: Attackers can extract sensitive data from backend databases, configuration files, or internal services.

✅ Authentication Bypass: Exploiting this flaw may allow unauthorized access to protected resources and administrative interfaces.

✅ Lateral Movement: Once initial access is gained, attackers can pivot to internal systems and escalate privileges.

How to Fix and Mitigate CVE-2016-3645

1. Apply Vendor Patches: Upgrade affected components to their latest, non-vulnerable versions immediately.
2. Implement Input Validation: Ensure all user-supplied data is validated, sanitized, and type-checked before processing.
3. Deploy Runtime Protection: Use Precogs continuous monitoring to detect exploitation attempts in real time.
4. Audit Dependencies: Review and update all third-party libraries and transitive dependencies.

Defending with Precogs AI

Symantec Antivirus Decomposer engine contains an integer overflow vulnerability when unpacking TNEF files. Attackers send a crafted email attachment that triggers memory corruption during the scan, executing code as SYSTEM. Precogs Binary Analysis identifies hazardous arithmetic operations preceding memory allocations.

Use Precogs to continuously scan your codebase, binaries, APIs, and infrastructure for this vulnerability class and related attack patterns. Our AI-powered detection engine combines static analysis with threat intelligence to identify exploitable weaknesses before attackers do.

Start scanning with Precogs →

Vulnerability Code Signature

Attack Data Flow

Vulnerable Code Pattern

# ❌ VULNERABLE: Unsanitized Input Flow
def process_request(request):
    user_input = request.GET.get('data')
    # Taint sink: processing untrusted data
    execute_logic(user_input)
    return {"status": "success"}

Secure Code Pattern

# ✅ SECURE: Input Validation & Sanitization
def process_request(request):
    user_input = request.GET.get('data')
    
    # Sanitized boundary check
    if not is_valid_format(user_input):
        raise ValueError("Invalid input format")
        
    sanitized_data = sanitize(user_input)
    execute_logic(sanitized_data)
    return {"status": "success"}

How Precogs Detects This

Precogs AI Analysis Engine maps untrusted input directly to execution sinks to catch complex application security vulnerabilities.\n