Versions mentioned in the description apply to the upstream
Remediation section below for
Debian:9 relevant versions.
Exim 4 before 4.94.2 allows Heap-based Buffer Overflow in queue_run via two sender options: -R and -S. This may cause privilege escalation from exim to root.
exim4 to version 4.89-2+deb9u8 or higher.