Arbitrary command execution in FreeBSD - #VU826

 

Arbitrary command execution in FreeBSD - #VU826

Published: October 10, 2016 / Updated: October 11, 2016


Vulnerability identifier: #VU826
CSH Severity: High
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber
CVE-ID: N/A
CWE-ID: CWE-20
Exploitation vector: Remote access
Exploit availability: No public exploit available
Vendor: FreeBSD Foundation
Affected software:
FreeBSD

Detailed vulnerability description

The vulnerability allows a remote unauthenticated user to execute arbitrary commands on the target system.
The weakness occurs in portsnap and exists due to insufficicient validation of downloaded tar files. By sending a specially crafted tar file attackers can cause arbitrary commands execution. A malicious user possessing elevated privileges is able to compromise the system completely.
Successful exploitation of the vulnerability leads to arbitrary command execution on the vulnerable system.

Remediation

Update patched versions:
- 10.x (https://security.FreeBSD.org/patches/SA-16:30/portsnap-10.patch);
- 9.3 (https://security.FreeBSD.org/patches/SA-16:30/portsnap-9.3.patch).

Sources