CVE-2020-6821

Cuando se lee desde áreas parcial o completamente fuera del recurso fuente con el método <code>copyTexSubImage</code> de WebGL, la especificación requiere que los valores devueltos sean cero. Anteriormente, esta memoria no fue inicializada, conllevando a una divulgación de datos potencialmente confidenciales. Esta vulnerabilidad afecta a Thunderbird versiones anteriores a 68.7.0, Firefox ESR versiones anteriores a 68.7 y Firefox versiones anteriores a 75.

The Mozilla Foundation Security Advisory describes this flaw as: When reading from areas partially or fully outside the source resource with WebGL's copyTexSubImage method, the specification requires the returned values be zero. Previously, this memory was uninitialized, leading to potentially sensitive data disclosure.

Multiple security issues were discovered in Firefox. If a user were tricked in to opening a specially crafted website, an attacker could potentially exploit these to cause a denial of service, obtain sensitive information, or execute arbitrary code. It was discovered that extensions could obtain auth codes from OAuth login flows in some circumstances. If a user were tricked in to installing a specially crafted extension, an attacker could potentially exploit this to obtain access to the user's account. Various other issues were also addressed.