Sylpheed-Claws before 2.2.2 and Sylpheed before 2.2.6 allow remote attackers to bypass the URI check functionality and makes it easier to conduct phishing attacks via a URI that begins with a space character.

Stack-based buffer overflow in the ldif_get_line function in ldif.c of Sylpheed before 2.1.6 allows user-assisted attackers to execute arbitrary code by having local users import LDIF files with long lines.

The IMAP Client for Sylpheed 0.8.11 allows remote malicious IMAP servers to cause a denial of service (crash) via certain large literal size values that cause either integer signedness errors or integer overflow errors.