Privilege escalation in FreeBSD Capsicum

1) Permissions, Privileges, and Access Controls

EUVDB-ID: #VU82982

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-2023-5369

CWE-ID: CWE-264 - Permissions, Privileges, and Access Controls

Exploit availability: No

Description

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

The vulnerability exists due to the copy_file_range system call in Capsicum checks only for CAP_READ and CAP_WRITE capabilities on the input and output file descriptors. A local user can read and write data to an arbitrary location within the file corresponding to that file descriptor.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

FreeBSD: 13.2

External links

http://security.FreeBSD.org/advisories/FreeBSD-SA-23:13.capsicum.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.