Research shows that 20% of apps on unofficial stores are potentially fraudulent.

Ethical hackers at Mobisec have warned that 20 per cent of apps on unofficial stores are potentially fraudulent.

These apps may contain security vulnerabilities or have been modified to steal user data. The sectors most affected include logistics, media, mass retail, entertainment, transportation and gaming. AppSentry, Mobisec’s product, can help companies detect these threats.

Treviso, 18 June 2025 – These are the digital spaces in which apps can be downloaded, including those not available on official stores. These may be outdated versions that are compatible with older smartphones or have unlocked premium features, which is a violation in itself, or they may be reached through fraudulent links. While they are very popular in the Android environment, those dedicated to iOS systems have also emerged in the last twelve months. The problem is that 20 percent of the apps in these unofficial stores are potentially fraudulent.

Ethical hackers from Mobisec, a Treviso-based mobile cybersecurity company, used AppSentry — a proprietary tool developed to allow companies to monitor the presence of their apps on unofficial stores (both Android and iOS) — to conduct this analysis. For the analysis, 122 apps from different industries were searched on 56 stores, with a focus on the Android environment.

The study found that 9.3% of the apps had a different name to the original, which suggests that other changes may have been made, likely of a malicious nature. A further 3.4% were found on stores that exclusively host modified apps, suggesting that their code has also been ‘tweaked’. Finally, Mobisec detected malicious behaviour within 9% of apps on unofficial stores that had been tampered with.

The logistics sector is among the most affected: 67 per cent of apps on unofficial stores, including those of major shipping companies, have features that could potentially make them malicious. The media and news sector follows closely behind, with 50 percent of apps — including those of major Italian newspapers — triggering AppSentry alerts. This is followed by public services (33 percent), including those related to healthcare and local government; entertainment (32 percent), including major Italian and international video streaming platforms; transportation and mobility (31 percent), including several cases among local public transport companies; and large-scale retail (29 percent). Messaging apps (27 percent) and gaming-related apps (25 percent) are also among the most affected.

Among the fraudulent versions of apps that AppSentry has identified in unofficial stores are several accessibility-related apps. These are apps that allow users with disabilities to fully enjoy mobile content, such as reading text or describing pictures. These fraudulent apps are particularly dangerous because they access critical functions; for example, they help a blind person to correctly enter a PIN on a bank’s app.

Users who install these apps on their devices face several risks. The least harmful risk is that of enriching malicious agents through the advertising displayed on these apps. The more serious risks concern the possibility of unethical hackers stealing sensitive data, such as credit card details, and targeting users with more effective phishing campaigns based on their monitored habits.

Mobisec’s tool can also alert companies to outdated versions of their apps in the stores, which may be made available to users with older smartphone models. Older versions of apps may expose users to security flaws fixed in subsequent updates, thus putting those using outdated versions at risk.

“The mere presence of an app on an unofficial store is not necessarily negative: it’s a natural occurrence in a system as diverse as the mobile one” says Simone Rebeschini, CEO of Mobisec. “The real problem arises when these apps contain malicious code, are outdated, or are used for fraud and other violations. This causes damage not only to users who download them, but also to companies in terms of customer trust and brand reputation. In this sense, protecting your brand today also means knowing which stores your app is in, how it is being used and whether it is being manipulated. Mobisec offers businesses a real-time radar system to reduce the likelihood of malicious attacks against them and their customers.”