Description

The Mira hormone monitor device firmware accepts a 0x01 write from any BLE central without authentication, causing the device to reboot into bootloader mode. An attacker could cause a denial-of-service condition or disrupt ovulation tracking and fertility monitoring workflow.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "6.5",
  "pubDate": "2026-08-11T22:18:49.740Z",
  "pubdate": "2026-08-11T22:18:49.740Z",
  "executiveSummary": "An unauthenticated denial-of-service vulnerability exists within the Bluetooth Low Energy (BLE) interface of the Mira hormone monitor device firmware. The flaw stems from the firmware's unvalidated acceptance of a specific 0x01 write command sent by any arbitrary BLE central device without requiring prior authentication or authorization.\nSuccessful exploitation of this vulnerability allows an unauthorized attacker within radio proximity to force the target device to unexpectedly reboot into bootloader mode. This disruptive behavior effectively halts normal device operation, resulting in a denial-of-service condition that interrupts critical ovulation tracking and fertility monitoring workflows for the user.\nThe risk implications are high for availability and functional integrity, as the attack requires minimal attacker capabilities—specifically, standard BLE scanning and connection capabilities within wireless range—and zero authentication or user interaction. Remediation requires firmware updates to enforce strict access control and authentication checks on critical control points over the BLE interface.",
  "technicalDetails": "The vulnerability resides within the firmware handling routines of the Mira hormone monitor Bluetooth Low Energy (BLE) communication stack. The root cause of the security flaw is the absence of proper authentication and authorization checks for specific administrative or control-plane write operations exposed over the BLE GATT profile.\nSpecifically, the vulnerable component processes incoming write requests from any connected BLE central device. When an unauthenticated central transmits a 0x01 write command to the device, the firmware lacks input validation or identity verification to confirm whether the sender possesses the appropriate privileges to execute system-level commands. Upon receiving this specific byte sequence, the firmware execution flow redirects abnormally, forcing the hardware to immediately reboot into its low-level bootloader mode.\nThe attack flow proceeds as follows: First, an attacker utilizes standard BLE tooling to scan for and identify a nearby active Mira hormone monitor device. Second, the attacker establishes an active BLE connection with the target peripheral device. Third, bypassing any requirement for pairing, bonding, or authentication, the attacker issues a GATT write request containing the 0x01 payload to the vulnerable characteristic or service handle. Finally, the target device receives the payload, processes the unauthenticated command, and immediately reboots into bootloader mode, terminating normal application execution.\nBecause the vulnerability is exposed over the wireless medium via the BLE interface, any attacker within physical radio range can repeatedly trigger the reboot condition. This prevents the device from completing its intended biological monitoring functions, leading to persistent denial of service and disrupting the continuous data collection necessary for accurate ovulation tracking and fertility analysis."
}