CVE-2018-3728: Prototype Pollution in hoek
Summary
CVE-2018-3728: Prototype Pollution in hoek. Affects hoek across 2 version ranges.
< 4.2.1
>= 5.0.0, < 5.0.3
Fixed in 4.2.1 or 5.0.3, depending on the release line you run. How to fix ↓
Also tracked for
- node-hoek · Debian:11
The same CVE-2018-3728 is tracked separately for each ecosystem and vendor. Its fix information is the same; the package and affected versions differ.
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Background
Hoek is an npm package that provides a set of utility functions commonly used in other Node.js modules. It is designed to handle various tasks such as merging objects, cloning objects, and manipulating data structures. However, versions of hoek prior to 4.2.1 and 5.0.3 are vulnerable to a prototype pollution attack.
Vulnerability Detail
The vulnerability in hoek arises from the merge function, as well as the applyToDefaults and applyToDefaultsWithShallow functions that internally use merge. When these functions are provided with an unvalidated payload created from a JSON string containing the __proto__ property, a prototype pollution attack can occur. This allows an attacker to overwrite existing properties, potentially leading to a denial of service.
How To Fix
Latest published version: 6.1.3 as of 22 Oct 2026
npm install hoek@6.1.3Upgrading to it may include breaking changes; the versions below are the minimum fixed release for this vulnerability.
If you can't move to the latest
The minimum fixed version depends on the release line you run.
-
< 4.2.14.2.1npm install hoek@4.2.1 -
>= 5.0.0, < 5.0.35.0.3npm install hoek@5.0.3
Tip — Not sure which release line you're on? Vulert can find the fix for the version you are using. Scan free →
Workaround
If updating to a patched version is not immediately feasible, a workaround can be implemented by validating and sanitizing any JSON payloads before passing them to the affected functions. This can be done by explicitly checking for the presence of the __proto__ property and rejecting payloads that contain it.
Conclusion
The vulnerability in hoek can be mitigated by updating to a patched version or implementing a workaround. It is crucial to address this issue promptly to prevent potential denial of service attacks. For further support on vulnerability remediation, please contact DevNack.com.
See every vulnerability recorded for hoek →
FAQ
Hoek is an npm package that provides utility functions for handling various tasks in Node.js modules.
Prototype pollution is a vulnerability that allows an attacker to modify the prototype of an object, leading to unexpected behavior and potential security issues.
The merge function, as well as the applyToDefaults and applyToDefaultsWithShallow functions that internally use merge, are affected by this vulnerability.
The prototype pollution attack in hoek can lead to the overwriting of existing properties, potentially causing a denial of service.
Updating to a patched version of hoek is the recommended mitigation. Alternatively, you can implement a workaround by validating and sanitizing JSON payloads before passing them to the affected functions.
