Multiple stack-based buffer overflows in YPOPs! (aka YahooPOPS) 0.4 through 0.6 allow remote attackers to cause a denial of service (crash) and possibly execute arbitrary code via a long (1) POP3 USER command or (2) SMTP request.
Exploit prediction scoring system (EPSS) score
EPSS Score 0.863
EPSS Ranking 99.4%