Package Instance

lodash vulnerable to Code Injection via `_.template` imports key names
### Impact

The fix for [CVE-2021-23337](https://github.com/advisories/GHSA-35jh-r3h4-6jhm) added validation for the `variable` option in `_.template` but did not apply the same validation to `options.imports` key names. Both paths flow into the same `Function()` constructor sink.

When an application passes untrusted input as `options.imports` key names, an attacker can inject default-parameter expressions that execute arbitrary code at template compilation time.

Additionally, `_.template` uses `assignInWith` to merge imports, which enumerates inherited properties via `for..in`. If `Object.prototype` has been polluted by any other vector, the polluted keys are copied into the imports object and passed to `Function()`.

### Patches

Users should upgrade to version 4.18.0.

The fix applies two changes:
1. Validate `importsKeys` against the existing `reForbiddenIdentifierChars` regex (same check already used for the `variable` option)
2. Replace `assignInWith` with `assignWith` when merging imports, so only own properties are enumerated

### Workarounds

Do not pass untrusted input as key names in `options.imports`. Only use developer-controlled, static key names.

Prototype Pollution in lodash
Versions of `lodash` before 4.17.12 are vulnerable to Prototype Pollution.  The function `defaultsDeep` allows 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.

Command Injection in lodash
`lodash` versions prior to 4.17.21 are vulnerable to Command Injection via the template function.