Curl_smtp_escape_eob in lib/smtp.c in curl before 7.61.0 has a heap-based buffer overflow that might be exploitable by an attacker who can control the data that curl transmits over SMTP with certain settings (i.e., use of a nonstandard --limit-rate argument or CURLOPT_BUFFERSIZE value). https://nvd.nist.gov/vuln/detail/CVE-2018-0500
