CVE-2021-21809

Public Exploit

Description

A command execution vulnerability exists in the default legacy spellchecker plugin in Moodle 3.10. A specially crafted series of HTTP requests can lead to command execution. An attacker must have administrator privileges to exploit this vulnerabilities.

Category

9.1
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 3.0 •
CVSS 2.0 •
EPSS 69.12% Top 5%
Third-Party Advisory packetstormsecurity.com Third-Party Advisory talosintelligence.com
Affected: n/a Moodle
Published at:
Updated at:

References

Link Tags
https://talosintelligence.com/vulnerability_reports/TALOS-2021-1277 third party advisory exploit
http://packetstormsecurity.com/files/164481/Moodle-SpellChecker-Path-Authenticated-Remote-Command-Execution.html exploit vdb entry third party advisory

Frequently Asked Questions

What is the severity of CVE-2021-21809?
CVE-2021-21809 has been scored as a critical severity vulnerability.
How to fix CVE-2021-21809?
To fix CVE-2021-21809, 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-2021-21809 being actively exploited in the wild?
It is possible that CVE-2021-21809 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~69% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-21809?
CVE-2021-21809 affects n/a Moodle.
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