Privilege escalation in FreeBSD vt console

1) Buffer overflow

EUVDB-ID: #VU59468

Risk: Low

CVSSv3.1: 6.8 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-29632

CWE-ID: CWE-119 - Memory corruption

Exploit availability: No

Description

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

The vulnerability exists due to a boundary error in vt console when processing the highlight buffer while text is scrolling on the console. A local user can trigger buffer overflow and overwrite data structures, associated with the system console or other kernel memory.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

FreeBSD: 12.0 - 13.0 RC5-p1

External links

http://www.freebsd.org/security/advisories/FreeBSD-SA-22:01.vt.asc

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.