CVE-2018-11481 in IPC TL-IPC223(P)-6
Summary
by MITRE
TP-LINK IPC TL-IPC223(P)-6, TL-IPC323K-D, TL-IPC325(KP)-*, and TL-IPC40A-4 devices allow authenticated remote code execution via crafted JSON data because /usr/lib/lua/luci/torchlight/validator.lua does not block various punctuation characters.
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Analysis
by VulDB Data Team • 02/10/2020
The vulnerability identified as CVE-2018-11481 affects several TP-LINK IPC camera models including the TL-IPC223(P)-6, TL-IPC323K-D, TL-IPC325(KP)-*, and TL-IPC40A-4 devices. This represents a critical security flaw that enables authenticated remote code execution through manipulation of JSON data structures. The vulnerability stems from inadequate input validation within the device's Lua-based web interface component, specifically in the validator.lua file located at /usr/lib/lua/luci/torchlight/validator.lua. The flaw allows attackers with valid credentials to inject malicious data that bypasses security controls designed to prevent unauthorized system access.
The technical implementation of this vulnerability involves the improper handling of punctuation characters within JSON data validation routines. The validator.lua script fails to properly sanitize or block specific punctuation characters that could be leveraged to manipulate the device's processing logic. This weakness creates a path for attackers to execute arbitrary commands on the affected devices through crafted JSON payloads. The vulnerability is classified as an input validation flaw that directly relates to CWE-20, which addresses "Improper Input Validation" in software systems. The flaw allows for command injection attacks that can compromise the entire device and potentially provide attackers with persistent access to the network infrastructure.
From an operational perspective, this vulnerability presents significant risks to network security and device integrity. The authenticated nature of the exploit means that an attacker must first obtain valid credentials, but once achieved, they can execute arbitrary code on the affected devices. This capability allows for complete system compromise, enabling attackers to install malware, modify device configurations, access stored data, or use the compromised devices as entry points for further attacks within the network. The impact extends beyond individual device compromise to potentially affect entire surveillance networks, as these IP cameras often serve as critical components in security infrastructure. This vulnerability directly aligns with ATT&CK technique T1059.007 for "Command and Scripting Interpreter: Lua" and represents a path to privilege escalation and persistent access within network environments.
The recommended mitigation strategies include immediate firmware updates from TP-LINK to address the validation flaw in the validator.lua component, implementation of network segmentation to limit access to these devices, and enforcement of strong authentication controls including multi-factor authentication. Organizations should also consider network monitoring solutions that can detect anomalous JSON data patterns and implement strict access controls limiting who can access the device management interfaces. Additionally, regular security assessments of networked devices and continuous monitoring of device logs for suspicious activities are essential defensive measures. The vulnerability demonstrates the critical importance of input validation in embedded systems and web applications, particularly in security-critical devices where unauthorized access can have severe consequences for network security and privacy.