Multiple buffer overflows in (1) iso2022jp.c or (2) shiftjis.c for Courier-IMAP before 3.0.0, Courier before 0.45, and SqWebMail before 4.0.0 may allow remote attackers to execute arbitrary code "when Unicode character is out of BMP range."
SQL injection vulnerability in the PostgreSQL auth module for courier 0.40 and earlier allows remote attackers to execute SQL code via the user name.