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.

Affected: npm: lodash, RubyGems: lodash-rails

Versions of `lodash` before 4.17.5 are vulnerable to prototype pollution.

The vulnerable functions are 'defaultsDeep', 'merge', and 'mergeWith' which allow 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.

## Recommendation

Update to version 4.17.5 or later.

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Affected: Ubuntu:Pro:16.04:LTS: node-lodash, Ubuntu:Pro:18.04:LTS: node-lodash

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.