CVE-2021-3709 Apport file permission bypass through emacs byte compilation errors

What is CVE-2021-3709?

CVE-2021-3709 is a medium-severity vulnerability in Canonical apport, published on 1 Oct 2021. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

Function check_attachment_for_errors() in file data/general-hooks/ubuntu.py could be tricked into exposing private data via a constructed crash file. This issue affects: apport 2.14.1 versions prior to 2.14.1-0ubuntu3.29+esm8; 2.20.1 versions prior to 2.20.1-0ubuntu2.30+esm2; 2.20.9 versions prior to 2.20.9-0ubuntu7.26; 2.20.11 versions prior to 2.20.11-0ubuntu27.20; 2.20.11 versions prior to 2.20.11-0ubuntu65.3;

Weakness: CWE-22, CWE-538

Which versions are affected by CVE-2021-3709?

It affects 1 product.

Products include Canonical Apport.

How do I fix CVE-2021-3709?

Apply the vendor's patch.

Is CVE-2021-3709 being exploited?

There is no known exploitation of CVE-2021-3709 in the wild and no public exploit code.

Other vulnerabilities in Canonical apport

• CVE-2021-25682 apport improperly parses /proc/pid/status High 8.8
• CVE-2021-25683 apport improperly parses /proc/pid/stat High 8.8
• CVE-2021-25684 apport can be stalled by reading a FIFO High 8.8
• CVE-2021-3899 Race condition in Apport High 7.8
• CVE-2022-1242 Other in Apport High 7.8

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-hq94-g33h-jj2x, UBUNTU-CVE-2021-3709.