An issue was discovered in EspoCRM before 5.6.9

An issue was discovered in EspoCRM before 5.6.9. Stored XSS was executed when a attacker sends an attachment to admin with malicious JavaScript in the filename. This JavaScript executed when an admin selects the particular file from the list of all attachments. The attacker could inject the JavaScript inside the filename and send it to users, thus helping him steal victims' cookies (hence compromising their accounts).