The hook_process function in the plugin API for WeeChat 0.3.0 through 0.3.9.1 allows remote attackers to execute arbitrary commands via shell metacharacters in a command from a plugin, related to "shell expansion."

Heap-based buffer overflow in WeeChat 0.3.6 through 0.3.9 allows remote attackers to cause a denial of service (crash or hang) and possibly execute arbitrary code via crafted IRC colors that are not properly decoded.

Wee Enhanced Environment for Chat (aka WeeChat) 0.3.4 and earlier does not properly verify that the server hostname matches the domain name of the subject of an X.509 certificate, which allows man-in-the-middle attackers to spoof an SSL chat server via an arbitrary certificate, related to incorrect use of the GnuTLS API.

Wee Enhanced Environment for Chat (WeeChat) 0.2.6 allows remote attackers to cause a denial of service (crash) via an IRC PRIVMSG command containing crafted color codes that trigger an out-of-bounds read.