CVE-2014-7992 in IOS
Summary
by MITRE
The DLSw implementation in Cisco IOS does not initialize packet buffers, which allows remote attackers to obtain sensitive credential information from process memory via a session on TCP port 2067, aka Bug ID CSCur14014.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 09/01/2024
The vulnerability identified as CVE-2014-7992 represents a critical security flaw within Cisco IOS operating systems that affects the Data Link Switching protocol implementation. This weakness specifically targets the DLSw (Data Link Switching) functionality that enables transparent bridging of LAN segments across WAN connections, creating a potential pathway for unauthorized information disclosure through improperly managed memory resources.
The technical root cause of this vulnerability stems from the failure of the DLSw implementation to properly initialize packet buffers before processing incoming network traffic. When remote attackers establish connections to TCP port 2067, which serves as the designated port for DLSw operations, the uninitialized memory regions contain residual data from previous operations or system processes. This memory leakage creates a scenario where sensitive information including user credentials, system configuration details, and potentially cryptographic keys could be extracted from process memory through carefully crafted network requests.
The operational impact of this vulnerability extends beyond simple information disclosure to encompass potential privilege escalation and unauthorized system access. Attackers exploiting this flaw can gain access to process memory through network-based attacks without requiring physical access or local system credentials. This makes the vulnerability particularly dangerous as it can be exploited remotely from any location with network connectivity to the affected Cisco IOS device. The vulnerability affects multiple Cisco IOS versions and is classified under CWE-125 as an "Out-of-bounds Read" condition where memory is accessed beyond its allocated boundaries.
Security professionals should recognize this vulnerability as part of the broader category of memory corruption issues that fall under ATT&CK technique T1005 - Data from Local System and T1041 - Exfiltration Over C2 Channel. The attack vector specifically aligns with T1190 - Exploit Public-Facing Application, where network services are targeted for information extraction through protocol-specific vulnerabilities. Organizations running Cisco IOS devices with DLSw functionality must understand that this flaw creates an attack surface that can be exploited by threat actors without requiring advanced privileges or specialized tools beyond standard network reconnaissance and exploitation capabilities.
The recommended mitigations include immediate implementation of Cisco IOS patches and updates that properly initialize packet buffers within the DLSw implementation, disabling DLSw functionality on devices where it is not strictly required, and implementing network segmentation to limit access to TCP port 2067. Network administrators should also consider deploying intrusion detection systems capable of monitoring for anomalous traffic patterns on the affected port and implementing firewall rules that restrict access to only trusted sources. Additionally, organizations should conduct comprehensive vulnerability assessments to identify all affected devices and ensure proper network configuration to prevent unauthorized access to DLSw services that could expose sensitive credential information from system memory.