Mozilla Developer Iain Ireland discovered a missing type check during unboxed objects removal, resulting in a crash. We presume that with enough effort that it could be exploited to run arbitrary code. This vulnerability affects Thunderbird < 68.9.0, Firefox < 77, and Firefox ESR < 68.9.
77.0.1+build1-0ubuntu0.16.04.11:68.10.0+build1-0ubuntu0.16.04.177.0.1+build1-0ubuntu0.18.04.138.8.0~repack1-0ubuntu138.8.0~repack1-0ubuntu338.8.0~repack1-0ubuntu452.3.1-0ubuntu352.3.1-7fakesync152.8.1-0ubuntu0.18.04.152.9.1-0ubuntu0.18.04.11:68.10.0+build1-0ubuntu0.18.04.177.0.1+build1-0ubuntu0.20.04.152.9.1-1build152.9.1-1ubuntu368.5.0-1~fakesync68.5.0-2~fakesync68.6.0-168.6.0-1ubuntu11:68.10.0+build1-0ubuntu0.20.04.1Exploitability
AV:NAC:LPR:NUI:RScope
S:UImpact
C:HI:HA:HCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H