Description
assign-deep node module before 0.4.7 suffers from a Modification of Assumed-Immutable Data (MAID) vulnerability, which allows a malicious user to modify the prototype of "Object" via __proto__, causing the addition or modification of an existing property that will exist on all objects.
Remediation
References
https://hackerone.com/reports/310707
https://github.com/jonschlinkert/assign-deep/commit/19953a8c089b0328c470acaaaf6accdfcb34da11