Multiple security issues have been found in Thunderbird, which may lead to the execution of arbitrary code or denial of service.

For Debian 9 stretch, these problems have been fixed in version 1:78.4.0-1~deb9u1.

We recommend that you upgrade your thunderbird packages.

For the detailed security status of thunderbird please refer to its security tracker page at: https://security-tracker.debian.org/tracker/thunderbird

Further information about Debian LTS security advisories, how to apply these updates to your system and frequently asked questions can be found at: https://wiki.debian.org/LTS