CVE Vulnerabilities

CVE-2021-43400

Use After Free

Published: Nov 04, 2021 | Modified: Nov 04, 2025
CVSS 3.x
9.1
CRITICAL
Source:
NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
CVSS 2.x
6.4 MEDIUM
AV:N/AC:L/Au:N/C:P/I:P/A:N
RedHat/V2
RedHat/V3
9.1 MODERATE
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Ubuntu
MEDIUM
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An issue was discovered in gatt-database.c in BlueZ 5.61. A use-after-free can occur when a client disconnects during D-Bus processing of a WriteValue call.

Weakness

The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory “belongs” to the code that operates on the new pointer.

Affected Software

NameVendorStart VersionEnd Version
BluezBluez5.61 (including)5.61 (including)
BluezUbuntubionic*
BluezUbuntuesm-infra/bionic*
BluezUbuntuesm-infra/focal*
BluezUbuntuesm-infra/xenial*
BluezUbuntufocal*
BluezUbuntuhirsute*
BluezUbuntuimpish*
BluezUbuntutrusty*
BluezUbuntuxenial*

Potential Mitigations

References