CVE ID         : CVE-2009-2939 CVE-2011-0411 CVE-2011-1720

Several vulnerabilities were discovered in Postfix, a mail transfer
agent.  The Common Vulnerabilities and Exposures project identifies
the following problems:

CVE-2009-2939
        The postinst script grants the postfix user write access to
        /var/spool/postfix/pid, which might allow local users to
        conduct symlink attacks that overwrite arbitrary files.

CVE-2011-0411
        The STARTTLS implementation does not properly restrict I/O
        buffering, which allows man-in-the-middle attackers to insert
        commands into encrypted SMTP sessions by sending a cleartext
        command that is processed after TLS is in place.

CVE-2011-1720
        A heap-based read-only buffer overflow allows malicious
        clients to crash the smtpd server process using a crafted SASL
        authentication request.