CVE-2020-6807

Cuando un dispositivo fue cambiado mientras una secuencia estaba a punto de ser destruida, la tarea <code>stream-reinit</code> pudo haberse ejecutado después de que la secuencia fue destruida, causando un uso de la memoria previamente liberada y un bloqueo potencialmente explotable. Esta vulnerabilidad afecta a Thunderbird versiones anteriores a 68.6, Firefox versiones anteriores a 74, Firefox versiones anteriores a ESR68.6 y Firefox ESR versiones anteriores a 68.6.

The Mozilla Foundation Security Advisory describes this flaw as: When a device was changed while a stream was about to be destroyed, the `stream-reinit` task may have been executed after the stream was destroyed, causing a use-after-free and a potentially exploitable crash.

Multiple security issues were discovered in Thunderbird. If a user were tricked in to opening a specially crafted website in a browsing context, an attacker could potentially exploit these to cause a denial of service, obtain sensitive information, bypass security restrictions, bypass same-origin restrictions, conduct cross-site scripting attacks, or execute arbitrary code. Various other issues were also addressed.