Abrt: unsanitized systemd journal content written to dump directory files enables content injection
A content injection vulnerability was found in the ABRT post-create event handler scripts in libreport. The event script queries the systemd journal for log entries matching the crashed process and writes the results to files in the dump directory without sanitizing embedded control characters. A local user can inject arbitrary content into the journal output by embedding newline characters in syslog messages, controlling the content that root writes to dump directory files.
The following practices would help for avoiding exposure and mitigate this flaw:
- Disable or remove ABRT if it is not required. On RHEL 8 systems where ABRT is installed, it can be disabled with: systemctl disable --now abrtd.service abrt-journal-core.service abrt-oops.service abrt-xorg.service
- On Fedora systems, consider using systemd-coredump instead of ABRT for crash handling
- Restrict local user access to systems running ABRT, as this vulnerability requires local access
Exploits
Credits
Red Hat would like to thank Red Team (Deutsche Telekom Security GmbH) for reporting this issue.