Response header name interning does not have same-origin protections and these headers are stored in a global registry. This allows stored header names to be available cross-origin. This vulnerability affects Firefox < 55.
El internamiento de nombres de cabecera de respuesta no tiene protecciones del mismo origen y estas cabeceras se almacenan en un registro global. Esto permite que los nombres de cabecera almacenados estén disponibles mediante Cross-Origin. La vulnerabilidad afecta a Firefox en versiones anteriores a la 55.
USN-3391-1 fixed vulnerabilities in Firefox. The update introduced a performance regression with WebExtensions. 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 conduct cross-site scripting attacks, bypass sandbox restrictions, obtain sensitive information, spoof the origin of modal alerts, bypass same origin restrictions, read uninitialized memory, cause a denial of service via program crash or hang, or execute arbitrary code. Various other issues were also addressed.
