MEDIUM6.5
In neomutt and mutt, the To and Cc email headers are not validated by cryptographic signing which allows an attacker that intercepts a message to change their value and include himself as a one of the recipients to compromise message confidentiality.
CVSS 3.xMEDIUM 6.5
CVSS:3.x/CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N