Vulnerability Name:

CVE-2021-21367 (CCN-198171)

Assigned:2020-12-22
Published:2021-03-09
Updated:2021-03-23
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).
CVSS v3 Severity:8.1 High (CVSS v3.1 Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N)
7.1 High (Temporal CVSS v3.1 Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N/E:U/RL:O/RC:C)
Exploitability Metrics:Attack Vector (AV): Adjacent
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): None
Scope:Scope (S): Unchanged
Impact Metrics:Confidentiality (C): High
Integrity (I): High
Availibility (A): None
6.1 Medium (CCN CVSS v3.1 Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:L)
5.3 Medium (CCN Temporal CVSS v3.1 Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:L/E:U/RL:O/RC:C)
Exploitability Metrics:Attack Vector (AV): Adjacent
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): None
Scope:Scope (S): Changed
Impact Metrics:Confidentiality (C): Low
Integrity (I): None
Availibility (A): Low
CVSS v2 Severity:4.3 Medium (CVSS v2 Vector: AV:A/AC:M/Au:N/C:P/I:P/A:N)
Exploitability Metrics:Access Vector (AV): Adjacent_Network
Access Complexity (AC): Medium
Authentication (Au): None
Impact Metrics:Confidentiality (C): Partial
Integrity (I): Partial
Availibility (A): None
4.8 Medium (CCN CVSS v2 Vector: AV:A/AC:L/Au:N/C:P/I:N/A:P)
Exploitability Metrics:Access Vector (AV): Adjacent_Network
Access Complexity (AC): Low
Athentication (Au): None
Impact Metrics:Confidentiality (C): Partial
Integrity (I): None
Availibility (A): Partial
Vulnerability Type:CWE-863
CWE-863
Vulnerability Consequences:Bypass Security
References:Source: MITRE
Type: CNA
CVE-2021-21367

Source: XF
Type: UNKNOWN
switchboard-cve202121367-sec-bypass(198171)

Source: MISC
Type: Patch, Third Party Advisory
https://github.com/elementary/switchboard-plug-bluetooth/commit/86500e645a907538abafe5225b67cc12c03e7645

Source: MISC
Type: Release Notes, Third Party Advisory
https://github.com/elementary/switchboard-plug-bluetooth/releases/tag/2.3.5

Source: CCN
Type: Switchboard Bluetooth Plug GIT Repository
Incorrect Authorization in switchboard-plug-bluetooth

Source: CONFIRM
Type: Patch, Third Party Advisory
https://github.com/elementary/switchboard-plug-bluetooth/security/advisories/GHSA-5p3g-j69g-w2mq

Source: FEDORA
Type: Mailing List, Third Party Advisory
FEDORA-2021-7d55c00267

Source: FEDORA
Type: Mailing List, Third Party Advisory
FEDORA-2021-3dedd41a06

Source: FEDORA
Type: Mailing List, Third Party Advisory
FEDORA-2021-6210be0100

Vulnerable Configuration:Configuration 1:
  • cpe:/a:elementary:switchboard_bluetooth_plug:*:*:*:*:*:elementary_os:*:* (Version >= 2.3.0 and < 2.3.5)

    • Configuration 2:
  • cpe:/o:fedoraproject:fedora:32:*:*:*:*:*:*:*
  • OR cpe:/o:fedoraproject:fedora:33:*:*:*:*:*:*:*

    • * Denotes that component is vulnerable
    BACK
    elementary switchboard bluetooth plug *
    fedoraproject fedora 32
    fedoraproject fedora 33