Vulnerabilities > CVE-2020-27403 - Information Exposure vulnerability in TCL products

047910
CVSS 6.5 - MEDIUM
Attack vector
ADJACENT_NETWORK
Attack complexity
LOW
Privileges required
NONE
Confidentiality impact
HIGH
Integrity impact
NONE
Availability impact
NONE
low complexity
tcl
CWE-200
NVD
Published: 2020-11-10
Updated: 2021-07-21

Summary

A vulnerability in the TCL Android Smart TV series V8-R851T02-LF1 V295 and below and V8-T658T01-LF1 V373 and below by TCL Technology Group Corporation allows an attacker on the adjacent network to arbitrarily browse and download sensitive files over an insecure web server running on port 7989 that lists all files & directories. An unprivileged remote attacker on the adjacent network, can download most system files, leading to serious critical information disclosure. Also, some TV models and/or FW versions may expose the webserver with the entire filesystem accessible on another port. For example, nmap scan for all ports run directly from the TV model U43P6046 (Android 8.0) showed port 7983 not mentioned in the original CVE description, but containing the same directory listing of the entire filesystem. This webserver is bound (at least) to localhost interface and accessible freely to all unprivileged installed apps on the Android such as a regular web browser. Any app can therefore read any files of any other apps including Android system settings including sensitive data such as saved passwords, private keys etc.

Vulnerable Configurations

Part Description Count
OS
Tcl
7
Hardware
Tcl
7

Common Weakness Enumeration (CWE)

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Subverting Environment Variable Values
    The attacker directly or indirectly modifies environment variables used by or controlling the target software. The attacker's goal is to cause the target software to deviate from its expected operation in a manner that benefits the attacker.
  • Footprinting
    An attacker engages in probing and exploration activity to identify constituents and properties of the target. Footprinting is a general term to describe a variety of information gathering techniques, often used by attackers in preparation for some attack. It consists of using tools to learn as much as possible about the composition, configuration, and security mechanisms of the targeted application, system or network. Information that might be collected during a footprinting effort could include open ports, applications and their versions, network topology, and similar information. While footprinting is not intended to be damaging (although certain activities, such as network scans, can sometimes cause disruptions to vulnerable applications inadvertently) it may often pave the way for more damaging attacks.
  • Exploiting Trust in Client (aka Make the Client Invisible)
    An attack of this type exploits a programs' vulnerabilities in client/server communication channel authentication and data integrity. It leverages the implicit trust a server places in the client, or more importantly, that which the server believes is the client. An attacker executes this type of attack by placing themselves in the communication channel between client and server such that communication directly to the server is possible where the server believes it is communicating only with a valid client. There are numerous variations of this type of attack.
  • Browser Fingerprinting
    An attacker carefully crafts small snippets of Java Script to efficiently detect the type of browser the potential victim is using. Many web-based attacks need prior knowledge of the web browser including the version of browser to ensure successful exploitation of a vulnerability. Having this knowledge allows an attacker to target the victim with attacks that specifically exploit known or zero day weaknesses in the type and version of the browser used by the victim. Automating this process via Java Script as a part of the same delivery system used to exploit the browser is considered more efficient as the attacker can supply a browser fingerprinting method and integrate it with exploit code, all contained in Java Script and in response to the same web page request by the browser.
  • Session Credential Falsification through Prediction
    This attack targets predictable session ID in order to gain privileges. The attacker can predict the session ID used during a transaction to perform spoofing and session hijacking.

References