TAIPEI (Taiwan News) — Taiwan’s cybersecurity agency has warned travelers to check who operates eSIM services before buying cut-rate plans from unfamiliar sellers.
The Administration for Cyber Security under the Ministry of Digital Affairs said some low-priced travel eSIMs can send mobile data through third-party routes, including Chinese telecom networks, per CNA.
The agency said an eSIM profile is not the same as an app with access to a phone. It stores a number and encrypted telecom credentials, and does not by itself read photos, contacts, passwords, or Line conversations.
The risk lies with the seller and the path a user’s data takes. If unencrypted information passes through a country where traffic can be monitored, browsing records or other exposed data could be intercepted.
Travelers should be cautious when an eSIM needs a separate app for activation. Apps that seek access to contacts, photos, Bluetooth, or location deserve extra scrutiny, and users should download them through Google Play or Apple’s App Store when possible, according to the report.
The agency advised users to buy from platforms with clear contact details, customer support, and a credible reputation. Buyers should also ask which carrier outside Taiwan actually hosts the network, rather than relying only on the seller’s brand name.
When using a new overseas connection, users should check that websites start with "https://" and show a lock icon, per the report. QR codes for installing eSIMs should be destroyed after installation or stored securely and not shared.
Warning signs include missing app chat records, sudden spikes in mobile data use, login alerts from unfamiliar locations, unexpected verification codes, or password-change notices. Users who see these signs should disable the eSIM’s mobile data and roaming, remove the eSIM profile and app, revoke sensitive permissions, delete cached data, change key passwords, and force logouts from other devices, CNA reported.
For people who need an eSIM, the agency recommended services handled directly by a major carrier in the destination country, so traffic connects locally instead of detouring through a third location. It said domestic carrier roaming with the user’s original number remains safer than SIM or eSIM services from unclear sources.
