CVE 2007-1267
Sylpheed 2.2.7 and earlier does not properly use the --status-fd argument when invoking GnuPG, which prevents Sylpheed from visually distinguishing between signed and unsigned portions of OpenPGP messages with multiple components, which allows remote attackers to forge the contents of a message without detection.
See the 
CVE page on Mitre.org
for more details.
