CVE-2021-21425

Public Exploit
Unauthenticated Arbitrary YAML Write/Update leads to Code Execution

Description

Grav Admin Plugin is an HTML user interface that provides a way to configure Grav and create and modify pages. In versions 1.10.7 and earlier, an unauthenticated user can execute some methods of administrator controller without needing any credentials. Particular method execution will result in arbitrary YAML file creation or content change of existing YAML files on the system. Successfully exploitation of that vulnerability results in configuration changes, such as general site information change, custom scheduler job definition, etc. Due to the nature of the vulnerability, an adversary can change some part of the webpage, or hijack an administrator account, or execute operating system command under the context of the web-server user. This vulnerability is fixed in version 1.10.8. Blocking access to the `/admin` path from untrusted sources can be applied as a workaround.

Category

9.3
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 89.00% Top 5%
Third-Party Advisory packetstormsecurity.com Third-Party Advisory packetstormsecurity.com Third-Party Advisory github.com Third-Party Advisory pentest.blog
Affected: getgrav grav-plugin-admin
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2021-21425?
CVE-2021-21425 has been scored as a critical severity vulnerability.
How to fix CVE-2021-21425?
To fix CVE-2021-21425, 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-2021-21425 being actively exploited in the wild?
It is possible that CVE-2021-21425 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~89% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-21425?
CVE-2021-21425 affects getgrav grav-plugin-admin.
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