What’s Vulnerable › Vulnerabilities

CVE-2021-21809

• Severity: critical (CVSS 9.1 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 24.2% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2021-06-23 · updated 2026-06-17
• Weakness: CWE-78

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.

Affected products

• Moodle: 3.10.0

References

• http://packetstormsecurity.com/files/164481/Moodle-SpellChecker-Path-Authenticated-Remote-Command-Execution.html
• https://talosintelligence.com/vulnerability_reports/TALOS-2021-1277
• http://packetstormsecurity.com/files/164481/Moodle-SpellChecker-Path-Authenticated-Remote-Command-Execution.html
• https://talosintelligence.com/vulnerability_reports/TALOS-2021-1277

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