This PR was automatically created by Snyk using the credentials of a real user.
Snyk has created this PR to fix one or more vulnerable packages in the `yarn` dependencies of this project.
#### Changes included in this PR
- Changes to the following files to upgrade the vulnerable dependencies to a fixed version:
- package.json
- yarn.lock
- Adding or updating a Snyk policy (.snyk) file; this file is required in order to apply Snyk vulnerability patches.
[Find out more](https://support.snyk.io/hc/en-us/articles/360003891078-Snyk-patches-to-fix-vulnerabilities).
#### Note for [zero-installs](https://yarnpkg.com/features/zero-installs) users
If you are using the Yarn feature [zero-installs](https://yarnpkg.com/features/zero-installs) that was introduced in Yarn V2, note that this PR does not update the `.yarn/cache/` directory meaning this code cannot be pulled and immediately developed on as one would expect for a zero-install project - you will need to run `yarn` to update the contents of the `./yarn/cache` directory.
If you are not using zero-install you can ignore this as your flow should likely be unchanged.
#### Vulnerabilities that will be fixed
##### With a [Snyk patch](https://support.snyk.io/hc/en-us/articles/360003891078-Snyk-patches-to-fix-vulnerabilities#patches):
Severity | Priority Score (*) | Issue | Exploit Maturity
:-------------------------:|-------------------------|:-------------------------|:-------------------------
 | **579/1000** **Why?** Has a fix available, CVSS 7.3 | Prototype Pollution [npm:extend:20180424](https://snyk.io/vuln/npm:extend:20180424) | No Known Exploit
 | **636/1000** **Why?** Proof of Concept exploit, Has a fix available, CVSS 6.3 | Prototype Pollution [npm:hoek:20180212](https://snyk.io/vuln/npm:hoek:20180212) | Proof of Concept
 | **646/1000** **Why?** Mature exploit, Has a fix available, CVSS 5.2 | Uninitialized Memory Exposure [npm:stringstream:20180511](https://snyk.io/vuln/npm:stringstream:20180511) | Mature
(*) Note that the real score may have changed since the PR was raised.
Check the changes in this PR to ensure they won't cause issues with your project.
------------
**Note:** *You are seeing this because you or someone else with access to this repository has authorized Snyk to open fix PRs.*
For more information:
🧐 [View latest project report](https://app.snyk.io/org/richardwillars/project/0e802c6d-c61d-4073-8656-1188a241a291?utm_source=github&utm_medium=referral&page=fix-pr)
🛠 [Adjust project settings](https://app.snyk.io/org/richardwillars/project/0e802c6d-c61d-4073-8656-1188a241a291?utm_source=github&utm_medium=referral&page=fix-pr/settings)
📚 [Read more about Snyk's upgrade and patch logic](https://support.snyk.io/hc/en-us/articles/360003891078-Snyk-patches-to-fix-vulnerabilities)
[//]: # (snyk:metadata:{"prId":"3d1cf2dd-bad6-4195-99ab-2022268a84c9","prPublicId":"3d1cf2dd-bad6-4195-99ab-2022268a84c9","dependencies":[],"packageManager":"yarn","projectPublicId":"0e802c6d-c61d-4073-8656-1188a241a291","projectUrl":"https://app.snyk.io/org/richardwillars/project/0e802c6d-c61d-4073-8656-1188a241a291?utm_source=github&utm_medium=referral&page=fix-pr","type":"auto","patch":["npm:extend:20180424","npm:hoek:20180212","npm:stringstream:20180511"],"vulns":["npm:extend:20180424","npm:hoek:20180212","npm:stringstream:20180511"],"upgrade":[],"isBreakingChange":false,"env":"prod","prType":"fix","templateVariants":["priorityScore"],"priorityScoreList":[579,636,646],"remediationStrategy":"vuln"})
---
**Learn how to fix vulnerabilities with free interactive lessons:**
🦉 [Prototype Pollution](https://learn.snyk.io/lesson/prototype-pollution/?loc=fix-pr)
This PR was automatically created by Snyk using the credentials of a real user.
Snyk has created this PR to fix one or more vulnerable packages in the `yarn` dependencies of this project.
#### Changes included in this PR - Changes to the following files to upgrade the vulnerable dependencies to a fixed version: - package.json - yarn.lock - Adding or updating a Snyk policy (.snyk) file; this file is required in order to apply Snyk vulnerability patches. [Find out more](https://support.snyk.io/hc/en-us/articles/360003891078-Snyk-patches-to-fix-vulnerabilities). #### Note for [zero-installs](https://yarnpkg.com/features/zero-installs) users If you are using the Yarn feature [zero-installs](https://yarnpkg.com/features/zero-installs) that was introduced in Yarn V2, note that this PR does not update the `.yarn/cache/` directory meaning this code cannot be pulled and immediately developed on as one would expect for a zero-install project - you will need to run `yarn` to update the contents of the `./yarn/cache` directory. If you are not using zero-install you can ignore this as your flow should likely be unchanged. #### Vulnerabilities that will be fixed ##### With a [Snyk patch](https://support.snyk.io/hc/en-us/articles/360003891078-Snyk-patches-to-fix-vulnerabilities#patches): Severity | Priority Score (*) | Issue | Exploit Maturity :-------------------------:|-------------------------|:-------------------------|:-------------------------  | **579/1000****Why?** Has a fix available, CVSS 7.3 | Prototype Pollution
[npm:extend:20180424](https://snyk.io/vuln/npm:extend:20180424) | No Known Exploit  | **636/1000**
**Why?** Proof of Concept exploit, Has a fix available, CVSS 6.3 | Prototype Pollution
[npm:hoek:20180212](https://snyk.io/vuln/npm:hoek:20180212) | Proof of Concept  | **646/1000**
**Why?** Mature exploit, Has a fix available, CVSS 5.2 | Uninitialized Memory Exposure
[npm:stringstream:20180511](https://snyk.io/vuln/npm:stringstream:20180511) | Mature (*) Note that the real score may have changed since the PR was raised. Check the changes in this PR to ensure they won't cause issues with your project. ------------ **Note:** *You are seeing this because you or someone else with access to this repository has authorized Snyk to open fix PRs.* For more information: