- A security scientist found a way to pull all kinds of sensitive data from a call
- Among the data was also geo-location information
- The error was present since the beginning of 2023 but was now attached
O2 UK has established a vulnerability in its voltage and Wi-Fi call implementations that enabled malicious actors to detect people’s locations and other identifiers.
Back in 2017, the company introduced IP Multimedia Subsystem (IMS) service, called “4G Calling”. The service provides better sound quality and more reliable phone calls. However, Daniel Williams, a security researcher, recently analyzed the feature and discovered that during the call he was able to withdraw all kinds of information about his interlocutor right from the network.
This data includes IMSI, IMEI and cell location.
Use of a solution
“The answers I got from the network were extremely detailed and long, and were unlike something I had seen before on other networks,” Williams said in a detailed blog post. “The messages contained information such as the IMS/SIP server used by O2 (Mavenir UAG) along with version numbers, occasional error messages raised by the C ++ services, processing call information when something went wrong, and other troubleshooting information.”
Fortunately, the vulnerability was not present since the beginning of 2017, but was rather introduced in February 2023.
To get cell location, William’s network signal used the guru app on a Pixel 8 device. He pulled Raw IM’s signaling messages during a call and used them to find the last cell tower to which the call recipient connected. He then referred to this data with a map of cell towers that clarified a person’s location within 100 m2 of an urban environment. In a rural environment, however, the information was somewhat less accurate.
Williams said he reached out to O2 UK several times and got to begin with no answer. The company later reported that the question was resolved, which Williams also confirmed.
“Our engineering team has been working on and tested a solution for a number of weeks – we can confirm that this is now fully implemented and testing suggests that the correction has worked and our customers do not have to take any action,” Virgin Media O2 told Bleeping computer.
Via Bleeping computer
