Researchers from Positive Technologies Security discovered multiple vulnerabilities with GPRS Tunneling Protocol (GTP) that let attackers target network users. The GTP is the protocol used to transmit user data and control traffic on 2G, 3G, 4G, and 5G networks.
Attackers could exploit the vulnerability to intercept user data, conduct fraud, and to launch DoS attacks.
The vulnerabilities with GTP protocol directly impact 5G networks, “the risk level should be regarded as high: in some cases, an attack can be performed just by using a mobile phone.”
GTP Security Issues
Researchers conducted various security assessments between 2018–2019 against 28 telecom operators in Europe, Asia, Africa, and South America and confirmed the vulnerabilities with the GTP protocol.
All the tested networks are vulnerable to DoS, impersonation, and fraud. This would allow attackers to interfere with network devices, defraud operators, customers, impersonate users to access various resources.
With the impersonation attacks, a cybercriminal could use the identity of the subscriber to get authorized access to online services and to bypass two-factor authentication and to conduct other frauds.
The vulnerabilities could pose a serious risk for 5G users as they are non-standalone, and deployed on the EPC core network.
“The GTP protocol will also partially remain in standalone 5G architecture, so even when those networks are developed security will remain a key issue,” reads the report.
“Mass loss of communication is especially dangerous for 5G networks because its subscribers are IoT devices such as industrial equipment, Smart Homes, and city infrastructure.”
Researchers stated that network operators are putting only a few security measures to protect these kinds of attacks, also making configuration mistakes pose serious risks.
Operators are recommended to look closely at the GTP protocol, ensure filtering at the GTP level, and deploy purpose-made security solutions.