Mozilla Firefox 93, Mozilla Firefox ESR 78.15, Mozilla Firefox ESR 91.2, Thunderbird 78.15 and Thunderbird 91.2 : Mozilla developers and community members Andreas Pehrson and Christian Holler reported memory safety bugs present in Firefox 92 and Firefox ESR 91.2. 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.