CVE-2026-54231: 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. The event script queries the systemd journal for log entries matching the crashed process using journalctl with COMM and UID filters, and writes the results to files in the dump directory (e.g., varlogmessages). Any local user can pre-populate the systemd journal with entries whose COMM matches common process names (e.g., "sleep") by using prctl(PRSETNAME) and syslog(). By embedding newline characters (\n) in syslog messages, the attacker can inject arbitrary content that appears on its own line in the journalctl output. While the event script filters out audit lines, it does not sanitize syslog entries for embedded control characters or validate the content before writing it to dump directory files. This allows an attacker to control the content that root writes to files in the dump directory.

— Red Hat