USN-4171-6: Apport regression

12 November 2020

USN-4171-1 introduced a regression in Apport.

Releases

Packages

  • apport - automatically generate crash reports for debugging

Details

USN-4171-1 fixed vulnerabilities in Apport. The update caused a regression
when handling configuration files. This update fixes the problem, and also
introduces further hardening measures.

Original advisory details:

Kevin Backhouse discovered Apport would read its user-controlled settings
file as the root user. This could be used by a local attacker to possibly
crash Apport or have other unspecified consequences. (CVE-2019-11481)

Sander Bos discovered a race-condition in Apport during core dump
creation. This could be used by a local attacker to generate a crash report
for a privileged process that is readable by an unprivileged user.
(CVE-2019-11482)

Sander Bos discovered Apport mishandled crash dumps originating from
containers. This could be used by a local attacker to generate a crash
report for a privileged process that is readable by an unprivileged user.
(CVE-2019-11483)

Sander Bos discovered Apport mishandled lock-file creation. This could be
used by a local attacker to cause a denial of service against Apport.
(CVE-2019-11485)

Kevin Backhouse discovered Apport read various process-specific files with
elevated privileges during crash dump generation. This could could be used
by a local attacker to generate a crash report for a privileged process
that is readable by an unprivileged user. (CVE-2019-15790)

Update instructions

The problem can be corrected by updating your system to the following package versions:

Ubuntu 20.10
Ubuntu 20.04
Ubuntu 18.04
Ubuntu 16.04

In general, a standard system update will make all the necessary changes.