CVE-2020-26959

Durante el cierre del navegador, la disminución de la referencia podría haber ocurrido en un objeto previamente liberado, resultando en un uso de la memoria previamente liberada, una corrupción de la memoria y un bloqueo potencialmente explotable. Esta vulnerabilidad afecta a Firefox versiones anteriores a 83, Firefox ESR versiones anteriores a 78.5, y Thunderbird versiones anteriores a 78.5

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 across origins, bypass security restrictions, conduct phishing attacks, conduct cross-site scripting attacks, bypass Content Security Policy restrictions, conduct DNS rebinding attacks, or execute arbitrary code.