Privilege escalation in Ubuntu

1) Privilege escalation

EUVDB-ID: #VU7010

Risk: Low

CVSSv4.0: 1.1 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2017-9525

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

Exploit availability: No

Description

The vulnerability allows a local attacker to gain elevated privileges on the target system.

The weakness exists in Cron due to a flaw in the postinst maintainer script. A local attacker with crontab group privileges can conduct a symlink attack, bypass crontab privilege separation controls and gain root privileges on the target system.

Successful exploitation of the vulnerability results in privilege escalation.

Mitigation

Cybersecurity Help is currently unaware of any official patch addressing the vulnerability.

Vulnerable software versions

Ubuntu: 12.04 - 17.10

CPE2.3

• cpe:2.3:o:canonical:ubuntu:12.04:*:*:*:*:*:*:*
• cpe:2.3:o:canonical:ubuntu:14.04:*:*:*:*:*:*:*
• cpe:2.3:o:canonical:ubuntu:16.04:*:*:*:*:*:*:*
• cpe:2.3:o:canonical:ubuntu:16.10:*:*:*:*:*:*:*
• cpe:2.3:o:canonical:ubuntu:17.04:*:*:*:*:*:*:*
• cpe:2.3:o:canonical:ubuntu:17.10:*:*:*:*:*:*:*

External links

https://people.canonical.com/~ubuntu-security/cve/2017/CVE-2017-9525.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.