Format string vulnerability in MemeCode Software i.Scribe 1.88 through 2.00 before Beta9 allows remote SMTP servers to cause a denial of service (crash) and possibly execute arbitrary code via format string specifiers in a server response, which is not properly handled "when displaying the signon message."
https://www.exploit-db.com/exploits/7249
https://exchange.xforce.ibmcloud.com/vulnerabilities/46970