"value":"Inside the JavaScript parser, a cast of an integer to a narrower type can result in data read from outside the buffer being parsed. This usually results in a non-exploitable crash, but can leak a limited amount of information from memory if it matches JavaScript identifier syntax. This vulnerability affects Firefox < 56."
}
]
},
"problemtype":{
"problemtype_data":[
{
"description":[
{
"lang":"eng",
"value":"Integer truncation in the JavaScript parser"