The latest firmware in some Philips smart TV models opens an insecure Miracast wireless network, allowing potential attackers located in the signal range to control the TV remotely and perform unauthorized actions.
Researchers from Malta-based vulnerability research firm ReVuln recently published a video demonstration of what attackers can do after they connect to the insecure wireless networks of the affected Philips TVs. The potential attacks include: accessing the TV's configuration files; accessing files stored on USB devices attached to the TV; broadcasting video, audio and images to the TV; controlling the TVs via an external remote control application and stealing website authentication cookies from the TV's browser.
The insecure network is opened by Miracast, a feature that enables the wireless delivery of audio and video content to the TV screen from desktops, tablets, phones, and other devices.
The Philips TVs running vulnerable firmware versions open a wireless network connection with an identifier that starts with DIRECT-xy and can be accessed with a hard-coded password, the ReVuln security researchers said Friday via email.
"So basically you just connect directly to the TV via WiFi without restrictions," the researchers said. "Miracast is enabled by default and the password cannot be changed. We tried all the possible ways to reset the TV included those methods suggested in the Philips manual [...] but the TV just allows anyone to connect."
The TV doesn't use any additional security measures like generating a unique PIN for each wireless client asking for manual confirmation before authorizing incoming connections.
The problem was likely introduced a few months ago and only exists in newer firmware versions, the ReVuln researchers said. Some models tested in a shop didn't have this issue, but they were running older firmware, they said.
The researchers tested a Philips 55PFL6008S TV, but believe many 2013 models are also affected because they share the same firmware. For example, the 47PFL6158, 55PFL8008 and 84PFL9708 models use all the same firmware although they have different screen sizes, they said.
The insecure wireless access combined with a directory traversal vulnerability in the JointSpace service, which allows external programs to remotely control the TV, allows attackers to extract TV configuration files, media files located on the attached USB devices or authentication cookies for Gmail and other sites from the TV browser.
"The cookies of the Opera browser integrated in the TV and used for all the websites (including the TV apps) are all stored in one file with a fixed path and name, so it's easy to get all of them with one download," the researchers said.
With these cookies, attackers can potentially gain access to the online accounts of the TV owners. However, the success of such attempts depends on the additional security measures of each website.
The directory traversal vulnerability in JointSpace was publicly disclosed in September by researchers from a Berlin-based security consultancy firm called Schobert IT-Security Consulting. The flaw doesn't appear to have been fixed by Philips and still exists in the latest firmware version -- 173.46, according to the ReVuln researchers.
However, even if this vulnerability is patched, the insecure Miracast wireless network still enables other attacks, like transmitting attacker-controlled video and audio content to the TV or remotely controlling the TV through an external application.
"We recognize the security issue as reported by ReVuln linked to Miracast on the high-end 2013 Philips Smart TVs," said Eva Heller, head of global communications at TP Vision, a joint venture between Philips and TPV Technology that manufactures and sells Philips-branded TVs, in an emailed statement. "Our experts are looking into this and are working on a fix."
TP recommends that, in the meantime, consumers switch off the Wi-Fi Miracast function of the TV. To do this, they need to press the HOME button, navigate to Setup, select Network Settings, navigate to Wi-Fi Miracast and set that to OFF.