Several security issues were fixed in Thunderbird.
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)
12 July 2018
A security issue affects these releases of Ubuntu and its derivatives:
Several security issues were fixed in Thunderbird.
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)
The problem can be corrected by updating your system to the following package versions:
To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.
After a standard system update you need to restart Thunderbird to make all the necessary changes.