Roundcube Webmail through 1.3.9 mishandles Punycode xn-- domain names, leading to homograph attacks.

Afterlogic WebMail Pro 8.3.11, and WebMail in Afterlogic Aurora 8.3.11, allows Remote Stored XSS via an attachment name.

MDaemon Webmail (formerly WorldClient) has CSRF.

In Roundcube Webmail before 1.3.10, an attacker in possession of S/MIME or PGP encrypted emails can wrap them as sub-parts within a crafted multipart email. The encrypted part(s) can further be hidden using HTML/CSS or ASCII newline characters. This modified multipart email can be re-sent by the attacker to the intended receiver. If the receiver replies to this (benign looking) email, they unknowingly leak the plaintext of the encrypted message part(s) back to the attacker.

Mailtraq WebMail version 2.17.7.3550 has Persistent Cross Site Scripting (XSS) via the body of an e-mail message. To exploit the vulnerability, the victim must open an email with malicious Javascript inserted into the body of the email as an iframe.

Roundcube before 1.3.7 mishandles GnuPG MDC integrity-protection warnings, which makes it easier for attackers to obtain sensitive information, a related issue to CVE-2017-17688. This is associated with plugins/enigma/lib/enigma_driver_gnupg.php.

steps/mail/func.inc in Roundcube before 1.3.8 has XSS via crafted use of <svg><style>, as demonstrated by an onload attribute in a BODY element, within an HTML attachment.

The OpenPGP specification allows a Cipher Feedback Mode (CFB) malleability-gadget attack that can indirectly lead to plaintext exfiltration, aka EFAIL. NOTE: third parties report that this is a problem in applications that mishandle the Modification Detection Code (MDC) feature or accept an obsolete packet type, not a problem in the OpenPGP specification

In Roundcube from versions 1.2.0 to 1.3.5, with the archive plugin enabled and configured, it's possible to exploit the unsanitized, user-controlled "_uid" parameter (in an archive.php _task=mail&_mbox=INBOX&_action=plugin.move2archive request) to perform an MX (IMAP) injection attack by placing an IMAP command after a %0d%0a sequence. NOTE: this is less easily exploitable in 1.3.4 and later because of a Same Origin Policy protection mechanism.

roundcube version 1.3.4 and earlier contains an Insecure Permissions vulnerability in enigma plugin that can result in exfiltration of gpg private key. This attack appear to be exploitable via network connectivity.