Critical severity · published Jun 23, 2021
CVE-2021-21809
A command execution vulnerability exists in the default legacy spellchecker plugin in Moodle 3.10
9.1
CVSS
24.2%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
High
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)24.2% · higher than 98% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MO
Moodle · Moodle
3.10.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-21809
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-21809
Exploit
http://packetstormsecurity.com/files/164481/Moodle-SpellChecker-Path-Authenticated-Remote-Command-Execution.html
Exploit
https://talosintelligence.com/vulnerability_reports/TALOS-2021-1277
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