CVE-2005-3803 in IP Phone
Summary
by MITRE
Cisco IP Phone (VoIP) 7920 1.0(8) contains certain hard-coded ("fixed") public and private SNMP community strings that cannot be changed, which allows remote attackers to obtain sensitive information.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 04/20/2018
The vulnerability identified as CVE-2005-3803 affects Cisco IP Phone 7920 VoIP device running firmware version 1.0(8) and potentially other versions within the same release. This represents a critical security flaw that stems from the device's implementation of Simple Network Management Protocol (SNMP) with hardcoded community strings. The issue resides in the device's default configuration where both public and private SNMP community strings are embedded within the firmware code rather than being dynamically generated or configurable by administrators. This design flaw creates a persistent security risk that affects the device's ability to maintain secure network management communications.
The technical implementation of this vulnerability involves the use of fixed SNMP community strings that remain unchanged regardless of network deployment requirements or security policies. These hardcoded credentials allow unauthorized remote actors to establish SNMP connections to the device and extract sensitive information including device configuration details, operational statistics, and potentially other network-relevant data. The vulnerability specifically impacts the device's management interface and exposes it to reconnaissance activities that can reveal network topology, device inventory, and operational parameters that would normally be protected through proper access controls. This flaw directly violates fundamental security principles of authentication and access control, creating an attack surface that can be exploited by any remote attacker who knows or can guess these fixed community strings.
The operational impact of this vulnerability extends beyond simple information disclosure to create potential escalation paths for more sophisticated attacks. Remote attackers can leverage the hardcoded SNMP credentials to perform unauthorized device management operations, potentially leading to configuration changes, denial of service conditions, or even device compromise. The vulnerability affects the device's ability to maintain secure communications with network management systems and creates opportunities for attackers to conduct network reconnaissance activities that could reveal additional attack vectors within the network infrastructure. This issue particularly impacts organizations deploying Cisco IP Phone 7920 devices in enterprise environments where VoIP security is paramount and unauthorized access to phone systems can lead to significant operational disruptions and potential data breaches.
Organizations should immediately implement mitigations that include disabling SNMP functionality on affected devices when not required for management purposes, implementing network segmentation to isolate VoIP devices from critical network segments, and deploying network monitoring solutions to detect unauthorized SNMP access attempts. The vulnerability aligns with CWE-798, which specifically addresses the use of hard-coded credentials in software, and represents a clear violation of the principle of least privilege in network security management. Security professionals should consider implementing network access control lists to restrict SNMP traffic to authorized management systems only, while also ensuring that any remaining SNMP functionality uses strong, dynamically generated community strings rather than fixed values. The ATT&CK framework categorizes this vulnerability under initial access and credential access techniques, emphasizing the importance of proper credential management and the elimination of default or hardcoded credentials in networked devices.