Multiple buffer overflows in E-Post Mail Server 4.10 and SPA-PRO Mail @Solomon 4.00 allow remote attackers to execute arbitrary code via a long username to the (1) AUTH PLAIN or (2) AUTH LOGIN SMTP commands, which is not properly handled by (a) EPSTRS.EXE or (b) SPA-RS.EXE; (3) a long username in the APOP POP3 command, which is not properly handled by (c) EPSTPOP4S.EXE or (d) SPA-POP3S.EXE; (4) a long IMAP DELETE command, which is not properly handled by (e) EPSTIMAP4S.EXE or (f) SPA-IMAP4S.EXE.