Prototype Pollution in 75lb deep-merge 1.1.1 allows attackers to execute arbitrary code or cause a Denial of Service (DoS) and cause other impacts via merge methods of lodash to merge objects.

The package ts-deepmerge before 2.0.2 are vulnerable to Prototype Pollution due to missing sanitization of the merge function.

deepmerge-ts is a typescript library providing functionality to deep merging of javascript objects. deepmerge-ts is vulnerable to Prototype Pollution via file deepmerge.ts, function defaultMergeRecords(). This issue has been patched in version 4.0.2. There are no known workarounds for this issue.

All versions of package merge-deep2 are vulnerable to Prototype Pollution via the mergeDeep() function.

The merge-deep library before 3.0.3 for Node.js can be tricked into overwriting properties of Object.prototype or adding new properties to it. These properties are then inherited by every object in the program, thus facilitating prototype-pollution attacks against applications using this library.

merge-deep node module before 3.0.1 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.