CVE-2026-84410: apport: Local privilege escalation to root via ldd execution on an attacker-controlled ExecutablePath in automatic crash report processing

In apport before 2.37.0, an improper privilege management vulnerability allows an unprivileged local attacker to gain root privileges on systems where automatic crash reporting is enabled. The automatic crash report processing pipeline runs as root and executes ldd on the attacker-controlled ExecutablePath field of a crash file placed in the world-writable /var/crash directory, causing the dynamic loader to load and execute an attacker-supplied audit module specified by the ELF's DTAUDIT tag. This allows an attacker to execute arbitrary code with root privileges and fully compromise the affected system.