Skip to content
Patch Next
Sign inAdd to your agent

← Actionable
Medium, CVSS 6.3

phpservermon is vulnerable to CRLF Injection

CVE-2021-4097GHSA-8qv8-fq5w-p966

What to do

Vendor response not established. Follow the primary source's mitigation guidance and check back for a fix.

This page has no inventory attached, so it cannot say whether you are affected. A vendor fix is not proof that your deployment is fixed.

Add to your agent

Affected packages

  • Packagist phpservermon/phpservermon

    Affected
    <= 3.5.2
    Fixed in
    no fixed version recorded

Sources

Severity and exploitation
Exploitation
No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.
CVSS
6.3 · CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L
EPSS
  • CVE-2021-4097: 0.87% estimated exploitation activity in the next 30 days; percentile 58.90 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.
Source description

As published by the source; long descriptions are shortened.

phpservermon is vulnerable to Improper Neutralization of CRLF Sequences.

Dates and revisions
Published by the source
Last modified by the source
Source last checked
  1. Revision 1 · created ·

    Published from ghsa record GHSA-8qv8-fq5w-p966

Agent brief

Preview the exact text before you copy it. Commands are read-only suggestions; review them before running anything.

# Patch Next advisory brief: CVE-2021-4097

Advisory: phpservermon is vulnerable to CRLF Injection
IDs: CVE-2021-4097, GHSA-8qv8-fq5w-p966
Record: https://patchnext.com/advisories/cve-2021-4097 (revision 1, source checked 26 Oct 2026, 14:04 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 6.3)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor response not established. A vendor fix does not mean a deployment is fixed.

## Affected components
- Packagist phpservermon/phpservermon: affected <= 3.5.2

## Suggested inspection (read-only)
- Packagist phpservermon/phpservermon: check the installed version with your package manager.

## Supported action
No complete vendor fix is recorded. Follow the primary source's mitigation guidance and check this record again before closing anything.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on phpservermon/phpservermon.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-8qv8-fq5w-p966 (GitHub-reviewed advisory GHSA-8qv8-fq5w-p966 lists affected ranges: Packagist phpservermon/phpservermon >=0 <=3.5.2)

Commands are suggestions: review each one before running it.

Loading voting…