CVE-2021-28428

Description

File upload vulnerability in HorizontCMS before 1.0.0-beta.3 via uploading a .htaccess and *.hello files using the Media Files upload functionality. The original file upload vulnerability (CVE-2020-27387) was remediated by restricting the PHP extensions; however, we confirmed that the filter was bypassed via uploading an arbitrary .htaccess and *.hello files in order to execute PHP code to gain RCE.

Category

9.8
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.41%
Third-Party Advisory github.com
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://github.com/ttimot24/HorizontCMS product
https://github.com/ttimot24/HorizontCMS/commit/9c4d6827cbe96decec6834d53660e14ab2bf8838 third party advisory patch

Frequently Asked Questions

What is the severity of CVE-2021-28428?
CVE-2021-28428 has been scored as a critical severity vulnerability.
How to fix CVE-2021-28428?
To fix CVE-2021-28428, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-28428 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-28428 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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