Improper Privilege Management

CVE-2019-15790

Low

3.3/10

Summary

Apport reads and writes information on a crashed process to /proc/pid with elevated privileges. Apport then determines which user the crashed process belongs to by reading /proc/pid through get_pid_info() in data/apport. An unprivileged user could exploit this to read information about a privileged running process by exploiting PID recycling. This information could then be used to obtain ASLR offsets for a process with an existing memory corruption vulnerability. The initial fix introduced regressions in the Python Apport library due to a missing argument in Report.add_proc_environ in apport/report.py. It also caused an autopkgtest failure when reading /proc/pid and with Python 2 compatibility by reading /proc maps. The initial and subsequent regression fixes are in 2.20.11-0ubuntu16, 2.20.11-0ubuntu8.6, 2.20.9-0ubuntu7.12, 2.20.1-0ubuntu2.22 and 2.14.1-0ubuntu3.29+esm3.

Attack Complexity: LOW
Attack Vector: LOCAL
Integrity Impact: NONE
Scope: UNCHANGED
User Interaction: NONE
Privileges Required: LOW
Confidentiality Impact: LOW
Availability Impact: NONE

CWE-269 - Improper Privilege Management

An effective privilege management infrastructure provides valid users with required access and privileges across heterogeneous technology environments. An application with a faulty privilege management infrastructure allows higher than authorized privileges or enables privilege escalation. This can lead to security incidents such as system infiltration, data breach, and complete system takeover.

References

Advisory Timeline

Published Apr 28, 2020