Privilege escalation in Postfix - #VU7062
Published: June 14, 2017 / Updated: March 20, 2020
Vulnerability identifier: #VU7062
CSH Severity: Low
CVSS v4: 4.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N]
CVE-ID: N/A
CWE-ID: CWE-427
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to escalate his privileges on the system.
The vulnerability exists due to Berkeley DB versions 2 and later try to read settings from a file DB_CONFIG in the current directory. A local user can create a specially crafted DB_CONFIG file and escalate his privileges on the system with Postfix set-gid programs (postdrop, postqueue) before they chdir to the Postfix queue directory, and with the postmap and postalias commands depending on whether the user's current directory is writable by other users.
Successful exploitation of the vulnerability may allow a local user to gain elevated privileges on the system.
The vulnerability exists due to Berkeley DB versions 2 and later try to read settings from a file DB_CONFIG in the current directory. A local user can create a specially crafted DB_CONFIG file and escalate his privileges on the system with Postfix set-gid programs (postdrop, postqueue) before they chdir to the Postfix queue directory, and with the postmap and postalias commands depending on whether the user's current directory is writable by other users.
Successful exploitation of the vulnerability may allow a local user to gain elevated privileges on the system.
Affected software
Postfix
Gentoo Linux
mail-mta/postfix
Gentoo Linux
mail-mta/postfix
Remediation
Update to version 3.2.2, 3.1.6, 3.0.10 or 2.11.10
Postfix - addressed in versions 2.11.10, 3.0.10, 3.1.6, 3.2.2
mail-mta/postfix - update to 3.1.6
mail-mta/postfix - update to 3.1.6