OpenSMTPD before 6.6.4 allows local users to read arbitrary files (e.g., on some Linux distributions) because of a combination of an untrusted search path in makemap.c and race conditions in the offline functionality in smtpd.c.
- http://seclists.org/fulldisclosure/2020/Feb/28
- http://www.openwall.com/lists/oss-security/2020/02/24/4
- https://github.com/ARPSyndicate/cvemon
- https://github.com/DmitrijVC/OpenSMTPD-RS
- https://github.com/FssAy/OpenSMTPD-RS
- https://github.com/bcoles/local-exploits