claws-mail is vulnerable to denial of service (DoS). The vulnerability exists in imap_scan_tree_recursive
where a malicious IMAP server can trigger stack consumption because of unlimited recursion into subdirectories during a rebuild of the folder tree.
lists.fedoraproject.org/archives/list/[email protected]/message/3CRKHUOVTJBHT53J4CYU53PXYYQKSGEA/
lists.fedoraproject.org/archives/list/[email protected]/message/JUBLHUG2UCXVABAGN5FVTD3AB3YKE5NN/
lists.fedoraproject.org/archives/list/[email protected]/message/YNJIXYDMSXYDII4ERMQ4EEKZX64U3QR4/
www.thewildbeast.co.uk/claws-mail/bugzilla/show_bug.cgi?id=4313