Privilege escalation in Linux kernel

1) Race condition

EUVDB-ID: #VU55257

Risk: Low

CVSSv3.1: 6.1 [CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-32399

CWE-ID: CWE-362 - Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

Exploit availability: No

Description

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to a race condition  for removal of the HCI controller within net/bluetooth/hci_request.c in the Linux kernel. A local user can exploit the race and gain unauthorized access to sensitive information and escalate privileges on the system.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Linux kernel: before 5.12.3

External links

http://github.com/torvalds/linux/commit/e2cb6b891ad2b8caa9131e3be70f45243df82a80
http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=e2cb6b891ad2b8caa9131e3be70f45243df82a80
http://www.openwall.com/lists/oss-security/2021/05/11/2
http://security.netapp.com/advisory/ntap-20210622-0006/
http://lists.debian.org/debian-lts-announce/2021/06/msg00019.html
http://lists.debian.org/debian-lts-announce/2021/06/msg00020.html

Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

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