Synopsis
The remote Ubuntu host is missing a security-related patch.
Description
Multiple security issues were discovered in Thunderbird. If a user were tricked in to opening a specially crafted website in a browsing context, an attacker could potentially exploit these to cause a denial of service, bypass CORS restrictions, obtain sensitive information, or execute arbitrary code. (CVE-2018-12359, CVE-2018-12360, CVE-2018-12362, CVE-2018-12363, CVE-2018-12364, CVE-2018-12365, CVE-2018-12366)
It was discovered that S/MIME and PGP decryption oracles can be built with HTML emails. An attacker could potentially exploit this to obtain sensitive information. (CVE-2018-12372)
It was discovered that S/MIME plaintext can be leaked through HTML reply/forward. An attacker could potentially exploit this to obtain sensitive information. (CVE-2018-12373)
It was discovered that forms can be used to exfiltrate encrypted mail parts by pressing enter in a form field. An attacker could potentially exploit this to obtain sensitive information. (CVE-2018-12374).
Note that Tenable Network Security has extracted the preceding description block directly from the Ubuntu security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.
Solution
Update the affected thunderbird package.