JavaScript code could be executed within the application when a victim viewed a malicious email or attachment, potentially leading to JWT token theft. Metasploit & Proof of Concept (PoC)
The exploit has been extensively documented and tested by security research firms: Confirmed Targets: Tested and verified as working on Build 6919 and Build 6970. Exploit Modules: A dedicated module is available via the Metasploit Framework exploit/windows/http/smartermail_rce Public Proofs of Concept:
When a client application interacts with these endpoints, data is passed over a TCP socket connection via serialized .NET objects. The software automatically deserializes this incoming, raw binary data without validating its source, integrity, or structure. smartermail 6919 exploit
While CVE-2019-7214 was the initial critical flaw that brought notoriety to build 6919, the security story of SmarterMail has continued to develop. Attackers and security researchers have identified a series of severe vulnerabilities that follow a similar pattern of authentication bypasses and unauthenticated RCE. These newer flaws have been actively exploited in the wild, highlighting that the risks associated with vulnerable SmarterMail systems are not just legacy issues but an ongoing and escalating threat.
: Tools like ysoserial.net format a command payload packaged in a serialized binary formatter container (such as a TypeConfuseDelegate or PropertyChangedEventArgs gadget chain). JavaScript code could be executed within the application
Build 6919 is a "golden" target for this specific exploit because it falls squarely within the vulnerable range. The Metasploit module (a popular penetration testing framework) for CVE-2019-7214 was successfully tested and verified to work against SmarterMail Build 6919.
By mid-2021, most responsible hosting providers had forced updates or applied virtual patches via web application firewalls (WAFs). Today, a scan for the 6919 exploit returns mostly honeypots—decoy servers set up by security researchers to study attacker behavior. These newer flaws have been actively exploited in
A public module for this exploit is available in the Metasploit Framework .
A dedicated exploit module is available in the Metasploit Framework to automate this attack. : exploit/windows/http/smartermail_rce Key Settings : RHOSTS : Target server IP. RPORT : 17001 (default). PAYLOAD : Typically a Windows meterpreter shell. 🔧 Remediation
The vulnerability is present in SmarterMail 16.x versions and was not fully addressed until the release of in early 2019. While newer builds like 9511 and 9518 have addressed more recent critical threats (such as CVE-2025-52691 and CVE-2026-23760), many legacy systems still running 2018-era builds remain vulnerable to this original deserialization flaw. Mitigation and Defense CVE-2019-7214 - NVD