Overview
The vulnerability in focus, CVE-2025-55972, affects a TCL Smart TV running a vulnerable UPnP/DLNA MediaRenderer implementation. The flaw can lead to a remote, unauthenticated Denial of Service (DoS) condition, posing significant threats to the affected device’s functionality and the user experience.
Vulnerability Summary
CVE ID: CVE-2025-55972
Severity: High (7.5 CVSS Score)
Attack Vector: Network
Privileges Required: None
User Interaction: None
Impact: Potential system compromise or data leakage; loss of device functionality
Affected Products
Product | Affected Versions
TCL Smart TV | All versions running a vulnerable UPnP/DLNA MediaRenderer implementation
How the Exploit Works
An attacker can exploit this vulnerability by sending a flood of malformed or oversized SetAVTransportURI SOAP requests to the UPnP control endpoint of the TCL Smart TV. This flood of requests causes the device to become unresponsive, disrupting all forms of TV operation. The denial persists as long as the attack continues, and manual user control or even reboots do not restore the device’s functionality unless the attack ceases.
Conceptual Example Code
Below is a conceptual example of how the vulnerability might be exploited. This example represents a malicious HTTP request.
POST /upnp/control/mediarenderer1 HTTP/1.1
Host: target-smarttv.com
Content-Type: text/xml; charset="utf-8"
SOAPAction: "urn:schemas-upnp-org:service:AVTransport:1#SetAVTransportURI"
0
[overly-long or malformed URI]
DD:upnp-org:av:2