Summary
Successful exploitation of this vulnerability could allow an attacker to read and write arbitrary handle values and change clinical readings, which could result in taking control of the device and lead to patient harm.
The following versions of Fourth Frontier Frontier X Mobile Application, Frontier X2 are affected:
- Frontier X Android application vers
- Frontier X IOS application vers
- Frontier X2 vers:all/*
- Frontier X IOS application vers
| CVSS | Vendor | Equipment | Vulnerabilities |
|---|---|---|---|
| v3 8.8 | Fourth Frontier | Fourth Frontier Frontier X Mobile Application, Frontier X2 | Missing Authentication for Critical Function |
Background
- Critical Infrastructure Sectors: Healthcare and Public Health
- Countries/Areas Deployed: Worldwide
- Company Headquarters Location: United States
Vulnerabilities
CVE-2026-5768
The Frontier X2 device allows unauthenticated BLE read/write access to critical GATT characteristics without enforcing pairing authentication or authorization. This allows attackers within BLE range to perform unauthorized control of device functions, including starting/stopping activities, triggering vibrations, causing denial-of-service conditions, and fuzzing characteristic values to induce unexpected behavior. Additionally, the Frontier X mobile application lacks proper BLE device authentication, allowing attackers to impersonate a legitimate Frontier X2 device and connect to the application. By cloning BLE advertisements and exposing expected GATT characteristics, attackers can manipulate activity states and inject fabricated health telemetry such as breathing rate, heart rate, strain, and other health-related data into the mobile application.
Affected Products
Fourth Frontier Frontier X Mobile Application, Frontier X2
Fourth Frontier
Fourth Frontier Frontier X Android application:
known_affected
Remediations
Mitigation
Fourth Frontier is aware of the vulnerability and is working on a fix. Users are encouraged to reach out to Fourth Frontier directly for assistance. https://fourthfrontier.com/pages/contact-usl.
https://fourthfrontier.com/pages/contact-us
Mitigation
Frontier X/X2 devices can connect to only one app at a time; users should first connect the Frontier X/X2 device using the Frontier X app and then start the activity.
Relevant CWE: CWE-306 Missing Authentication for Critical Function
Metrics
| CVSS Version | Base Score | Base Severity | Vector String |
|---|---|---|---|
| 3.1 | 8.8 | HIGH | CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
Acknowledgments
- Shakir Zari and Jerin Sunny reported this vulnerability to CISA
Legal Notice and Terms of Use
This product is provided subject to this Notification (https://www.cisa.gov/notification) and this Privacy & Use policy (https://www.cisa.gov/privacy-policy).
Recommended Practices
CISA recommends users take defensive measures to minimize the risk of exploitation of this vulnerability.
Minimize network exposure for all control system devices and/or systems, ensuring they are not accessible from the internet.
Locate control system networks and remote devices behind firewalls and isolating them from business networks.
When remote access is required, use more secure methods, such as Virtual Private Networks (VPNs), recognizing VPNs may have vulnerabilities and should be updated to the most current version available. Also recognize VPN is only as secure as the connected devices.
CISA reminds organizations to perform proper impact analysis and risk assessment prior to deploying defensive measures.
CISA also provides a section for control systems security recommended practices on the ICS webpage on cisa.gov/ics. Several CISA products detailing cyber defense best practices are available for reading and download, including Improving Industrial Control Systems Cybersecurity with Defense-in-Depth Strategies.
CISA encourages organizations to implement recommended cybersecurity strategies for proactive defense of ICS assets.
Additional mitigation guidance and recommended practices are publicly available on the ICS webpage at cisa.gov/ics in the technical information paper, ICS-TIP-12-146-01B--Targeted Cyber Intrusion Detection and Mitigation Strategies.
Organizations observing suspected malicious activity should follow established internal procedures and report findings to CISA for tracking and correlation against other incidents.
No known public exploitation specifically targeting this vulnerability has been reported to CISA at this time. This vulnerability is not exploitable remotely.
Revision History
- Initial Release Date: 2026-05-28
| Date | Revision | Summary |
|---|---|---|
| 2026-05-28 | 1 | Initial Publication |