CVE-2017-8076 in TL-SG108E
Summary
by MITRE
On the TP-Link TL-SG108E 1.0, admin network communications are RC4 encoded, even though RC4 is deprecated. This affects the 1.1.2 Build 20141017 Rel.50749 firmware.
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Analysis
by VulDB Data Team • 09/20/2020
The TP-Link TL-SG108E 1.0 network switch presents a significant cryptographic vulnerability through its use of RC4 encryption for administrative communications despite RC4 being widely deprecated due to severe security weaknesses. This vulnerability affects firmware version 1.1.2 Build 20141017 Rel.50749 and represents a critical flaw in the device's security architecture. The implementation of RC4 encryption for administrative network traffic exposes the device to potential man-in-the-middle attacks and credential interception, as RC4 has known cryptographic weaknesses that make it susceptible to various attack vectors including key recovery and plaintext prediction attacks. The vulnerability stems from the device's failure to implement modern cryptographic standards for securing administrative communications, creating an attack surface that adversaries can exploit to gain unauthorized access to network management functions.
The technical flaw manifests in the device's protocol implementation where administrative network communications are encrypted using the RC4 stream cipher algorithm instead of more secure alternatives such as AES or TLS with modern cipher suites. This cryptographic weakness directly violates industry security best practices and standards, as RC4 has been deprecated since 2015 by major security organizations including NIST and IETF due to its susceptibility to bias attacks and key recovery vulnerabilities. The specific implementation in the TL-SG108E firmware demonstrates a failure to maintain current security standards, as RC4 has known weaknesses including predictable keystreams and statistical biases that can be exploited to recover plaintext communications. This flaw operates at the application layer of the network stack and specifically impacts the administrative interface communication protocols, making it particularly dangerous for network administrators who rely on these interfaces for device management.
The operational impact of this vulnerability extends beyond simple credential theft to encompass complete network compromise potential. An attacker who can intercept administrative communications can potentially gain full control over the switch configuration, modify network policies, redirect traffic, or establish persistent access points within the network infrastructure. The vulnerability creates a path for attackers to escalate privileges and move laterally within the network, as administrative access to network switches provides extensive control over network traffic flow and security policies. This represents a critical weakness in network security architecture, as network switches serve as fundamental infrastructure components that, when compromised, can provide attackers with significant control over network operations and security enforcement mechanisms. The vulnerability also violates the principle of least privilege by not implementing adequate cryptographic protection for administrative functions, creating a scenario where sensitive network management operations are transmitted in plaintext or with weak encryption.
Mitigation strategies for this vulnerability must address both immediate remediation and long-term security improvements. The primary recommendation involves upgrading the firmware to a version that implements modern cryptographic standards including TLS 1.2 with strong cipher suites or at minimum AES encryption for administrative communications. Network administrators should also implement additional security controls such as network segmentation to limit access to administrative interfaces, enforce strict access controls through firewall rules, and implement network monitoring to detect unusual administrative traffic patterns. The vulnerability demonstrates the importance of maintaining current firmware versions and implementing robust security policies that require regular security assessments of network infrastructure components. From an ATT&CK framework perspective, this vulnerability maps to techniques involving credential access and privilege escalation, while CWE classification would fall under CWE-327 (Use of a Broken or Risky Cryptographic Algorithm) and CWE-310 (Cryptographic Issues). Organizations should also consider implementing network access controls to restrict administrative access to the switch and ensure that only authorized personnel can access the device management interfaces, thereby reducing the attack surface for this specific vulnerability.