Versions of the package underscore-keypath from 0.0.11 are vulnerable to Prototype Pollution via the name argument of the setProperty() function. Exploiting this vulnerability is possible due to improper input sanitization which allows the usage of arguments like “__proto__”.

Underscore.deep is a collection of Underscore mixins that operate on nested objects. Versions of `underscore.deep` prior to version 0.5.3 are vulnerable to a prototype pollution vulnerability. An attacker can craft a malicious payload and pass it to `deepFromFlat`, which would pollute any future Objects created. Any users that have `deepFromFlat` or `deepPick` (due to its dependency on `deepFromFlat`) in their code should upgrade to version 0.5.3 as soon as possible. Users unable to upgrade may mitigate this issue by modifying `deepFromFlat` to prevent specific keywords which will prevent this from happening.

A Regular Expression Denial of Service (ReDOS) vulnerability was discovered in underscore-99xp v1.7.2 when the deepValueSearch function is called.

The package underscore from 1.13.0-0 and before 1.13.0-2, from 1.3.2 and before 1.12.1 are vulnerable to Arbitrary Code Injection via the template function, particularly when a variable property is passed as an argument as it is not sanitized.