CVE-2002-0309 in Enterprise Firewall
Summary
by MITRE
SMTP proxy in Symantec Enterprise Firewall (SEF) 6.5.x includes the firewall s physical interface name and address in an SMTP protocol exchange when NAT translation is made to an address other than the firewall, which could allow remote attackers to determine certain firewall configuration information.
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Analysis
by VulDB Data Team • 10/23/2024
The vulnerability identified as CVE-2002-0309 represents a significant information disclosure weakness within Symantec Enterprise Firewall version 6.5.x SMTP proxy functionality. This flaw occurs when the firewall performs network address translation operations where the destination address differs from the firewall's own address. The security implications stem from the proxy's tendency to expose internal network configuration details through protocol exchanges, creating an avenue for unauthorized information gathering that could aid subsequent attack vectors.
The technical mechanism behind this vulnerability involves the SMTP proxy component within SEF 6.5.x that processes email traffic when NAT translation occurs. When traffic is translated to an address that does not match the firewall's physical interface, the proxy includes identifying information about the firewall's network interface configuration within the SMTP protocol communication. This behavior violates fundamental security principles by inadvertently disclosing network topology information that should remain confidential.
This vulnerability directly relates to CWE-200, which addresses information exposure, and aligns with several ATT&CK tactics including TA0007 reconnaissance and TA0006 credential access. The flaw enables attackers to gather intelligence about the firewall's physical interface names and associated IP addresses, potentially revealing internal network structure and configuration details that would otherwise remain hidden from external observers. The information disclosed could include interface identifiers that help attackers understand the firewall's network layout and potentially identify other vulnerable components within the same network segment.
The operational impact of this vulnerability extends beyond simple information disclosure, as it provides attackers with valuable reconnaissance data that can be used to plan more sophisticated attacks. Network administrators who deploy SEF 6.5.x may find their internal network configurations exposed through seemingly benign SMTP protocol exchanges, creating opportunities for attackers to map network topologies and identify potential targets for further exploitation. This exposure is particularly concerning in environments where network segmentation is critical for maintaining security boundaries.
Organizations should implement immediate mitigations including updating to newer versions of Symantec Enterprise Firewall that address this information disclosure vulnerability, configuring the SMTP proxy to disable unnecessary interface information disclosure, and implementing network segmentation strategies that limit the exposure of sensitive configuration details. Additionally, network monitoring should be enhanced to detect unusual SMTP protocol exchanges that might indicate exploitation attempts. The vulnerability serves as a reminder of the importance of minimizing information leakage in security products and demonstrates how seemingly minor configuration details can create significant security risks when exposed through protocol implementations.