MGASA-2021-0407

Updated thunderbird packages fix security vulnerabilities:

Uninitialized memory in a canvas object could have caused an incorrect free() leading to memory corruption and a potentially exploitable crash (CVE-2021-29980).

Instruction reordering during JIT optimization resulted in a sequence of instructions that would cause an object to be incorrectly considered during garbage collection. This led to memory corruption and a potentially exploitable crash (CVE-2021-29984).

A use-after-free vulnerability in media channels could have led to memory corruption and a potentially exploitable crash (CVE-2021-29985).

A suspected race condition when calling getaddrinfo while resolving DNS names could have led to memory corruption and a potentially exploitable crash (CVE-2021-29986).

Thunderbird incorrectly treated an inline list-item element as a block element, resulting in an out of bounds read or memory corruption, and a potentially exploitable crash (CVE-2021-29988).

Mozilla developers Christoph Kerschbaumer, Simon Giesecke, Sandor Molnar, and Olli Pettay reported memory safety bugs present in Thunderbird ESR 78.12. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code (CVE-2021-29989).