# CVE-2021-39172

## Summary

- **CVE ID:** CVE-2021-39172
- **Severity:** HIGH
- **CVSS Score:** 8.8 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H)
- **CWE:** CWE-93
- **Published:** Aug 27, 2021
- **Last Modified:** Mar 13, 2026

## Description

Cachet is an open source status page system. Prior to version 2.5.1, authenticated users, regardless of their privileges (User or Admin), can exploit a new line injection in the configuration edition feature (e.g. mail settings) and gain arbitrary code execution on the server. This issue was addressed in version 2.5.1 by improving `UpdateConfigCommandHandler` and preventing the use of new lines characters in new configuration values. As a workaround, only allow trusted source IP addresses to access to the administration dashboard.

## Affected Products

- fiveai — Cachet (< 2.5.1)

## References

- [CNA](https://github.com/fiveai/Cachet/security/advisories/GHSA-9jxw-cfrh-jxq6)
- [CNA](https://github.com/fiveai/Cachet/releases/tag/v2.5.1)
- [CNA](https://blog.sonarsource.com/cachet-code-execution-via-laravel-configuration-injection/)

## Exploitation Prediction (EPSS)

- **EPSS Score:** 63.05%
- **EPSS Percentile:** 98.3

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_Exported from OnDuty AI Vulnerability Intelligence on 2026-09-18._