Mozilla Thunderbird 38.5.0 is yet another bugfix release that addresses multiple security issues discovered by Mozilla or third-party developers since the previous version of the software, which was announced at the end of November 2015.
Among these, we can mention an integer overflow in the playback of MP4 files on 64-bit builds of Thunderbird, an underflow through code inspection, another integer overflow, this time related to the allocation of huge textures, a cross-site reading attack through view-source URIs, as well as several memory safety issues.