Description
Versions of lodash before 4.17.11 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 {constructor: {prototype: {...}}} causing the addition or modification of an existing property that will exist on all objects.
Recommendation
Update the lodash package to the latest compatible version. Followings are version details:
- Affected version(s): < 4.17.11
- Patched version(s): 4.17.11
References
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See something that needs correcting? Let us knowUpdated August 12, 2025