Exim 4 before 4.94.2 allows Heap-based Buffer Overflow because it mishandles “-F ‘.(‘” on the command line, and thus may allow privilege escalation from any user to root. This occurs because of the interpretation of negative sizes in strncpy.
CWE-787
CVE-2020-28016
Exim 4 before 4.94.2 allows an off-by-two Out-of-bounds Write because “-F ”” is mishandled by parse_fix_phrase.
CVE-2020-28022
Exim 4 before 4.94.2 has Improper Restriction of Write Operations within the Bounds of a Memory Buffer. This occurs when processing name=value pairs within MAIL FROM and RCPT TO commands.
CVE-2020-28024
Exim 4 before 4.94.2 allows Buffer Underwrite that may result in unauthenticated remote attackers executing arbitrary commands, because smtp_ungetc was only intended to push back characters, but can actually push back non-character error codes such as EOF.
CVE-2020-28010
Exim 4 before 4.94.2 allows Out-of-bounds Write because the main function, while setuid root, copies the current working directory pathname into a buffer that is too small (on some common platforms).
CVE-2020-28011
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.