Incorrect Authorization
CVE-2021-21367
Summary
Switchboard Bluetooth Plug for elementary OS from version 2.3.0 and before version version 2.3.5 has an incorrect authorization vulnerability. When the Bluetooth plug is running (in discoverable mode), Bluetooth service requests and pairing requests are automatically accepted, allowing physically proximate attackers to pair with a device running an affected version of switchboard-plug-bluetooth without the active consent of the user. By default, elementary OS doesn't expose any services via Bluetooth that allow information to be extracted by paired Bluetooth devices. However, if such services (i.e. contact list sharing software) have been installed, it's possible that attackers have been able to extract data from such services without authorization. If no such services have been installed, attackers are only able to pair with a device running an affected version without authorization and then play audio out of the device or possibly present a HID device (keyboard, mouse, etc...) to control the device. As such, users should check the list of trusted/paired devices and remove any that are not 100% confirmed to be genuine. This is fixed in version 2.3.5. To reduce the likelihood of this vulnerability on an unpatched version, only open the Bluetooth plug for short intervals when absolutely necessary and preferably not in crowded public areas. To mitigate the risk entirely with unpatched versions, do not open the Bluetooth plug within switchboard at all, and use a different method for pairing devices if necessary (e.g. `bluetoothctl` CLI).
- LOW
- ADJACENT_NETWORK
- HIGH
- UNCHANGED
- NONE
- NONE
- HIGH
- NONE
CWE-863 - Incorrect Authorization
Authorization is a security mechanism performed by an application to grant or deny access to the requested resources by verifying the privileges of the user. When an application lacks effective authorization mechanisms, it enables unauthorized users to gain unintended privileges and illegitimate access to resources. Such a vulnerability may result in exposure of sensitive information, denial of service, arbitrary code execution, and complete system takeover.
References
Advisory Timeline
- Published