lodash node module before 4.17.5 suffers from a Modification of Assumed-Immutable Data (MAID) vulnerability via defaultsDeep, merge, and mergeWith functions, 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.
Exploitability
AV:NAC:LPR:LUI:NScope
S:UImpact
C:NI:HA:N6.5/CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:NOther