CVE-2017-6327 in Messaging Gateway
Summary
by MITRE
The Symantec Messaging Gateway before 10.6.3-267 can encounter an issue of remote code execution, which describes a situation whereby an individual may obtain the ability to execute commands remotely on a target machine or in a target process. In this type of occurrence, after gaining access to the system, the attacker may attempt to elevate their privileges.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 09/09/2024
The Symantec Messaging Gateway vulnerability identified as CVE-2017-6327 represents a critical remote code execution flaw that affects versions prior to 10.6.3-267. This vulnerability resides within the email security appliance's handling of specific input parameters, creating an avenue for malicious actors to execute arbitrary code on the target system. The flaw stems from insufficient validation of user-supplied data within the messaging gateway's processing pipeline, allowing attackers to inject and subsequently execute malicious commands through crafted input sequences. The vulnerability operates at the application layer and can be exploited without authentication, making it particularly dangerous as it eliminates the need for initial access credentials. This type of vulnerability falls under CWE-77 and aligns with ATT&CK technique T1059.001, which covers command and scripting interpreter execution. The impact extends beyond simple remote code execution as attackers can leverage this initial foothold to escalate privileges and establish persistent access within the network infrastructure.
The technical implementation of this vulnerability occurs when the messaging gateway processes incoming email messages or configuration data that contains malicious payloads designed to exploit the input validation weakness. Attackers can craft specially formatted emails or configuration parameters that, when processed by the vulnerable system, trigger code execution in the context of the messaging gateway service. This execution environment typically operates with elevated privileges, enabling attackers to gain system-level access to the underlying operating system. The vulnerability's exploitation pathway demonstrates a classic buffer overflow or injection attack vector where improper input sanitization allows attackers to manipulate the application's execution flow. The flaw's nature suggests that it may be related to improper handling of file uploads or parameter processing within the gateway's web interface or message processing components. Security researchers have documented that the vulnerability can be triggered through multiple vectors including HTTP requests, email parsing operations, and configuration management interfaces, making it highly versatile for exploitation across different attack scenarios.
The operational impact of CVE-2017-6327 extends far beyond immediate system compromise, as it provides attackers with a powerful foothold within enterprise email infrastructure. Organizations utilizing vulnerable Symantec Messaging Gateway appliances face significant risks including data exfiltration, lateral movement within the network, and potential establishment of persistent backdoors. The vulnerability's ability to execute commands remotely without authentication makes it particularly attractive to threat actors seeking to compromise email security systems that are often considered trusted network components. Once exploited, attackers can leverage the compromised gateway to monitor email traffic, modify message content, redirect communications, or use the appliance as a pivot point for attacking other systems within the same network segment. The privilege escalation capability inherent in this vulnerability means that attackers can move from initial access to system-level control, potentially enabling them to access sensitive corporate data, modify email policies, or disable security features. This vulnerability directly impacts the integrity and confidentiality of email communications, undermining the very security posture that organizations rely on for protecting their digital assets. The attack surface is particularly concerning as email gateways often sit at the intersection of internal and external network traffic, making them prime targets for attackers seeking to establish persistent access to enterprise environments.
Mitigation strategies for CVE-2017-6327 require immediate action to patch vulnerable systems with the vendor-supplied security updates. Organizations should prioritize updating their Symantec Messaging Gateway appliances to version 10.6.3-267 or later, which contains the necessary fixes for this vulnerability. Network segmentation and access controls should be implemented to limit exposure of the messaging gateway to untrusted networks, while monitoring systems should be configured to detect anomalous behavior patterns that may indicate exploitation attempts. Security teams should conduct thorough network scans to identify all instances of vulnerable software and implement additional security measures including web application firewalls and intrusion detection systems. The remediation process should also include reviewing and strengthening input validation procedures, implementing proper access controls, and establishing comprehensive monitoring protocols for email gateway activities. Organizations should consider conducting penetration testing to validate the effectiveness of their mitigations and ensure that no other vulnerabilities exist within their email security infrastructure. Regular security assessments and vulnerability management programs should be enhanced to prevent similar issues from occurring in the future, with particular attention to input validation and privilege management within email security appliances. The vulnerability serves as a reminder of the critical importance of maintaining up-to-date security patches and the potential consequences of failing to address known vulnerabilities in enterprise security infrastructure.