CVE-2021-39173

Name: CVE-2021-39173
Creator: NVD / NIST
Published: 2021-08-27T23:15:06.957+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 8.8/10EPSS 2.36%

Last modified Jun 17, 2026

CVE-2021-39173 is a high-severity vulnerability rated 8.8/10 on the CVSS scale. Cachet is an open source status page system. Prior to version 2.5.1 authenticated users, regardless of their privileges (User or Admin), can trick Cachet and install the instance again, leading to arbitrary code execution on the server. EPSS estimates a 2.36% chance of exploitation in the next 30 days.

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 trick Cachet and install the instance again, leading to arbitrary code execution on the server. This issue was addressed in version 2.5.1 by improving the middleware `ReadyForUse`, which now performs a stricter validation of the instance name. As a workaround, only allow trusted source IP addresses to access to the administration dashboard.

Metrics

CVSS 3.1

8.8/10

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS Probability

2.36%

81.6th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Catchethq	Catchet	< 2.5.1

References

https://blog.sonarsource.com/cachet-code-execution-via-laravel-configuration-injection/Exploit, Third Party Advisory
https://github.com/fiveai/Cachet/releases/tag/v2.5.1Release Notes, Third Party Advisory
https://github.com/fiveai/Cachet/security/advisories/GHSA-r67m-m8c7-jp83Third Party Advisory
https://blog.sonarsource.com/cachet-code-execution-via-laravel-configuration-injection/Exploit, Third Party Advisory
https://github.com/fiveai/Cachet/releases/tag/v2.5.1Release Notes, Third Party Advisory
https://github.com/fiveai/Cachet/security/advisories/GHSA-r67m-m8c7-jp83Third Party Advisory

Timeline

Published: Aug 27, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-39173?

How severe is CVE-2021-39173?

CVE-2021-39173 has a CVSS score of 8.8/10 (HIGH severity). The EPSS model estimates a 2.36% probability of exploitation in the next 30 days.

How do I fix CVE-2021-39173?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-39173?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST