SB2020022427 - Privilege escalation in Zsh
Published: February 24, 2020 Updated: March 19, 2020
Security Bulletin ID
SB2020022427
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 security vulnerability.
1) Improper Check for Dropped Privileges (CVE-ID: CVE-2019-20044)
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to Zsh fails to overwrite the saved uid, so the original privileges, dropped by the --no-PRIVILEGED option, can be restored by
executing MODULE_PATH=/dir/with/module zmodload with a module that calls
setuid(). A local user can execute arbitrary commands on the system with elevated privileges.
Remediation
Install update from vendor's website.