The AES-GCM implementation in WebCrypto API accepts 0-length IV when it should require a length of 1 according to the NIST Special Publication 800-38D specification. This might allow for the authentication key to be determined in some instances. This vulnerability affects Firefox < 56.
La implementación AES-GCM en WebCrypto API acepta 0-length IV cuando debería exigir una longitud de 1 de acuerdo con la especificación NIST Special Publication 800-38D. Esto podría permitir que se determine la clave de autenticación en algunas instancias. Esta vulnerabilidad afecta a las versiones anteriores a la 56 de Firefox.
USN-3435-1 fixed vulnerabilities in Firefox. The update caused the Flash plugin to crash in some circumstances. This update fixes the problem. 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 read uninitialized memory, obtain sensitive information, bypass phishing and malware protection, spoof the origin in modal dialogs, conduct cross-site scripting attacks, cause a denial of service via application crash, or execute arbitrary code. Martin Thomson discovered that NSS incorrectly generated handshake hashes. A remote attacker could potentially exploit this to cause a denial of service via application crash, or execute arbitrary code. Multiple security issues were discovered in WebExtensions. If a user were tricked in to installing a specially crafted extension, an attacker could potentially exploit these to download and open non-executable files without interaction, or obtain elevated privileges. Various other issues were also addressed.