It was discovered that process_crash() in data/apport in Canonical's Apport crash reporting tool may create crash files with incorrect group ownership, possibly exposing crash information beyond expected or intended groups.
Race condition in Canonical apport up to and including 2.32.0 allows a local attacker to leak sensitive information via PID-reuse by leveraging namespaces.
When handling a crash, the function `_check_global_pid_and_forward`, which detects if the crashing process resided in a container, was being called before `consistency_checks`, which attempts to detect if the crashing process had been replaced. Because of this, if a process crashed and was quickly replaced with a containerized one, apport could be made to forward the core dump to the container, potentially leaking sensitive information. `consistency_checks` is now being called before `_check_global_pid_and_forward`. Additionally, given that the PID-reuse race condition cannot be reliably detected from userspace alone, crashes are only forwarded to containers if the kernel provided a pidfd, or if the crashing process was unprivileged (i.e., if dump mode == 1).