#VU83407 Use-after-free in BlueZ - CVE-2021-43400

Vulnerability identifier: #VU83407

Vulnerability risk: Medium

CVSSv4.0: 3.7 [CVSS:4.0/AV:P/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-43400

CWE-ID: CWE-416

Exploitation vector: Local

Exploit availability: No

Vulnerable software:
BlueZ
Universal components / Libraries / Libraries used by multiple products

Vendor: BlueZ Project

Description

The vulnerability allows an attacker to compromise vulnerable system.

The vulnerability exists due to a use-after-free error in gatt-database.c on a gatt server if a client disconnects while a WriteValue call is being processed with D-Bus. An attacker with physical proximity to the system can trigger a use-after-free error and potentially execute arbitrary code.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

BlueZ: 4.0 - 5.61

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External links
https://git.kernel.org/pub/scm/bluetooth/bluez.git/commit/?id=838c0dc7641e1c991c0f3027bf94bee4606012f8
https://lists.debian.org/debian-lts-announce/2022/10/msg00026.html

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Q & A

Can this vulnerability be exploited remotely?

No. The attacker should have physical access to the system in order to successfully exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.