CVE-2021-29945

El JIT de WebAssembly podía calcular mal el tamaño de un tipo de retorno, lo que podía conllevar a una lectura nula y resultar en un bloqueo. *Nota: Este problema sólo afectaba a las plataformas x86-32. Otras plataformas no están afectadas. Esta vulnerabilidad afecta a Firefox ESR versiones anteriores a 78.10, Thunderbird versiones anteriores a 78.10 y Firefox versiones anteriores a 88

Multiple security issues were discovered in Thunderbird. If a user were tricked into opening a specially crafted website in a browsing context, an attacker could potentially exploit these to cause a denial of service, obtain sensitive information, spoof the UI, bypass security restrictions, or execute arbitrary code. It was discovered that extensions could open popup windows with control of the window title in some circumstances. If a user were tricked into installing a specially crafted extension, an attacker could potentially exploit this to spoof a website and trick the user into providing credentials. Various other issues were also addressed.