Mozilla: Use-after-free and use-after-scope logging XHR header errors (MFSA 2017-16)

A use-after-free and use-after-scope vulnerability when logging errors from headers for XML HTTP Requests XHR. This could result in a potentially exploitable crash. This vulnerability affects Firefox 54, Firefox ESR 52.2, and Thunderbird 52.2...

security flaw

Firefox before 1.0.7 and Mozilla Suite before 1.7.12 allows remote attackers to modify HTTP headers of XML HTTP requests via XMLHttpRequest, and possibly use the client to exploit vulnerabilities in servers or proxies, including HTTP request smuggling and HTTP request splitting...