functions/imap_general.php in SquirrelMail before 1.4.21 does not properly handle 8-bit characters in passwords, which allows remote attackers to cause a denial of service (disk consumption) by making many IMAP login attempts with different usernames, leading to the creation of many preferences files.
Multiple cross-site request forgery (CSRF) vulnerabilities in SquirrelMail 1.4.19 and earlier, and NaSMail before 1.7, allow remote attackers to hijack the authentication of unspecified victims via features such as send message and change preferences, related to (1) functions/mailbox_display.php, (2) src/addrbook_search_html.php, (3) src/addressbook.php, (4) src/compose.php, (5) src/folders.php, (6) src/folders_create.php, (7) src/folders_delete.php, (8) src/folders_rename_do.php, (9) src/folders_rename_getname.php, (10) src/folders_subscribe.php, (11) src/move_messages.php, (12) src/options.php, (13) src/options_highlight.php, (14) src/options_identities.php, (15) src/options_order.php, (16) src/search.php, and (17) src/vcard.php.
Multiple cross-site scripting (XSS) vulnerabilities in SquirrelMail 1.4.0 through 1.4.9 allow remote attackers to inject arbitrary web script or HTML via the (1) mailto parameter in (a) webmail.php, the (2) session and (3) delete_draft parameters in (b) compose.php, and (4) unspecified vectors involving "a shortcoming in the magicHTML filter."
Dynamic variable evaluation vulnerability in compose.php in SquirrelMail 1.4.0 to 1.4.7 allows remote attackers to overwrite arbitrary program variables and read or write the attachments and preferences of other users.
webmail.php in SquirrelMail 1.4.0 to 1.4.5 allows remote attackers to inject arbitrary web pages into the right frame via a URL in the right_frame parameter. NOTE: this has been called a cross-site scripting (XSS) issue, but it is different than what is normally identified as XSS.
Interpretation conflict in the MagicHTML filter in SquirrelMail 1.4.0 to 1.4.5 allows remote attackers to conduct cross-site scripting (XSS) attacks via style sheet specifiers with invalid (1) "/*" and "*/" comments, or (2) a newline in a "url" specifier, which is processed by certain web browsers including Internet Explorer.
CRLF injection vulnerability in SquirrelMail 1.4.0 to 1.4.5 allows remote attackers to inject arbitrary IMAP commands via newline characters in the mailbox parameter of the sqimap_mailbox_select command, aka "IMAP injection."