SB2018082320 - Privilege escalation in Ubuntu
Published: August 23, 2018 Updated: August 23, 2018
Security Bulletin ID
SB2018082320
CSH Severity
Low
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Local access
Highest impact
Code execution
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Privilege escalation (CVE-ID: CVE-2018-6557)
CWE-ID: CWE-264 - Permissions, Privileges, and Access Controls
CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
The vulnerability allows a local attacker to gain elevated privileges on the target system.
The vulnerability exists in the MOTD update script due to improper processing of temporary files. A local attacker can supply specially crafted symbolic links (symlinks) from a temporary file to a critical file on the system to overwrite files with administrator privileges.
Remediation
Install update from vendor's website.