This Verizon security flaw could let an attacker see your entire call history

A serious vulnerability discovered in Verizon’s Call Filter app has exposed the incoming call logs of potentially millions of users. Although the issue was resolved in March 2025, experts warn the consequences may still linger, especially for those at risk of targeted surveillance.

A flaw in the API exposed user call data

The bug was discovered in February 2025 by cybersecurity researcher Evan Connelly, who found that Verizon’s Call Filter app failed to verify the phone number of the requesting user. This allowed anyone with minimal technical knowledge to query the API and retrieve incoming call logs from other users’ devices. Because the flaw was in the API itself, not the app, it affected both iOS and Android versions.

A surveillance risk for high-profile targets

Connelly warned that while call metadata might seem harmless, it can be a “powerful surveillance tool in the wrong hands.” By accessing someone’s call log, an attacker could map out daily routines, identify frequent contacts, and infer personal or professional relationships. This raises red flags for individuals such as journalists, activists, or political figures who may be exposed to targeted monitoring.

Verizon patched the issue, but uncertainty remains

Verizon quietly fixed the vulnerability in March 2025, yet the company has not disclosed how long the data was accessible. This uncertainty means users should remain cautious about any unusual activity linked to their phone accounts. The scale of potential exposure remains unknown, given the app’s widespread use and integration into Verizon’s devices.