CVE-2020-26558 Security feature bypass in n/a

Medium 4.2 Published 24 May 2021 Updated 4 Nov 2025

A nearby attacker can bypass Bluetooth pairing authentication by reflecting keys to determine the Passkey bit-by-bit, allowing unauthorized device pairing.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Local or same network only
Victim action needed: Not needed
Fix: Available

What is CVE-2020-26558?

CVE-2020-26558 is a medium-severity vulnerability in Debian Debian Linux, published on 24 May 2021. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

Bluetooth LE and BR/EDR secure pairing in Bluetooth Core Specification 2.1 through 5.2 may permit a nearby man-in-the-middle attacker to identify the Passkey used during pairing (in the Passkey authentication procedure) by reflection of the public key and the authentication evidence of the initiating device, potentially permitting this attacker to complete authenticated pairing with the responding device using the correct Passkey for the pairing session. The attack methodology determines the Passkey value one bit at a time.

Weakness: CWE-287

Which versions are affected by CVE-2020-26558?

It affects 19 products.

Linux distribution packages (24)

`bluez-cups` Red Hat:enterprise_linux:8::appstream	All versions	`0:5.56-1.el8`
`bluez-cups-debuginfo` Red Hat:enterprise_linux:8::appstream	All versions	`0:5.56-1.el8`
`bluez-debuginfo` Red Hat:enterprise_linux:8::appstream	All versions	`0:5.56-1.el8`
`bluez-debugsource` Red Hat:enterprise_linux:8::appstream	All versions	`0:5.56-1.el8`
`bluez-hid2hci-debuginfo` Red Hat:enterprise_linux:8::appstream	All versions	`0:5.56-1.el8`
`bluez-libs-debuginfo` Red Hat:enterprise_linux:8::appstream	All versions	`0:5.56-1.el8`
`bluez-obexd-debuginfo` Red Hat:enterprise_linux:8::appstream	All versions	`0:5.56-1.el8`
`bluez` Red Hat:enterprise_linux:8::baseos	All versions	`0:5.56-1.el8`
`bluez-cups-debuginfo` Red Hat:enterprise_linux:8::baseos	All versions	`0:5.56-1.el8`
`bluez-debuginfo` Red Hat:enterprise_linux:8::baseos	All versions	`0:5.56-1.el8`
`bluez-debugsource` Red Hat:enterprise_linux:8::baseos	All versions	`0:5.56-1.el8`
`bluez-hid2hci` Red Hat:enterprise_linux:8::baseos	All versions	`0:5.56-1.el8`
`bluez-hid2hci-debuginfo` Red Hat:enterprise_linux:8::baseos	All versions	`0:5.56-1.el8`
`bluez-libs` Red Hat:enterprise_linux:8::baseos	All versions	`0:5.56-1.el8`
`bluez-libs-debuginfo` Red Hat:enterprise_linux:8::baseos	All versions	`0:5.56-1.el8`
`bluez-obexd` Red Hat:enterprise_linux:8::baseos	All versions	`0:5.56-1.el8`
`bluez-obexd-debuginfo` Red Hat:enterprise_linux:8::baseos	All versions	`0:5.56-1.el8`
`bluez-cups-debuginfo` Red Hat:enterprise_linux:8::crb	All versions	`0:5.56-1.el8`
`bluez-debuginfo` Red Hat:enterprise_linux:8::crb	All versions	`0:5.56-1.el8`
`bluez-debugsource` Red Hat:enterprise_linux:8::crb	All versions	`0:5.56-1.el8`
`bluez-hid2hci-debuginfo` Red Hat:enterprise_linux:8::crb	All versions	`0:5.56-1.el8`
`bluez-libs-debuginfo` Red Hat:enterprise_linux:8::crb	All versions	`0:5.56-1.el8`
`bluez-libs-devel` Red Hat:enterprise_linux:8::crb	All versions	`0:5.56-1.el8`
`bluez-obexd-debuginfo` Red Hat:enterprise_linux:8::crb	All versions	`0:5.56-1.el8`

Products include Bluetooth Bluetooth Core Specification, Debian Debian Linux, Fedoraproject Fedora, Intel Ac 1550 Firmware, Intel Ac 3165 Firmware, Intel Ac 3168 Firmware and 13 more.

How do I fix CVE-2020-26558?

Apply the vendor's patch.

Is CVE-2020-26558 being exploited?

There is no known exploitation of CVE-2020-26558 in the wild and no public exploit code.

All Debian Debian Linux vulnerabilities

Sources

Also known as A-174886838, ASB-A-174886838, DEBIAN-CVE-2020-26558, GHSA-7g33-jchx-2fjc, RHSA-2021:4432, UBUNTU-CVE-2020-26558.