deeply is vulnerable to Prototype Pollution in versions before 3.1.0. The function assign-deep could be tricked into adding or modifying properties of Object.prototype using using a proto payload.
[
{
"product": "deeply",
"vendor": "n/a",
"versions": [
{
"status": "affected",
"version": "All versions prior to version 3.1.0"
}
]
}
]