Staging Environment: Content and features may be unstable or change without notice.
Advisory details: github_osv / GHSA-c7jj-vfmr-j9mj
Advisory ID github_osv/GHSA-c7jj-vfmr-j9mj
Aliases CVE-2021-21809
Summary Moodle command execution vulnerability exists in the default legacy spellchecker plugin A command execution vulnerability exists in the default legacy spellchecker plugin in a few Moodle multiple specific versions. A specially crafted series of HTTP requests can lead to command execution. An attacker must have administrator privileges to exploit this vulnerabilities.
Status Published
Exploitability 2.0
Weighted Severity 8.2
Risk 10.0
Affected and Fixed Packages Package Details
Introduced and Fixed Package Commit Patches Package Commit Patches Details
Weaknesses (1)
CWE-732 Incorrect Permission Assignment for Critical Resource
System Score Found at
cvssv3.1 9.1 https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2022/05/GHSA-c7jj-vfmr-j9mj/GHSA-c7jj-vfmr-j9mj.json
generic_textual CRITICAL
Reference id Reference type URL
http://packetstormsecurity.com/files/164481/Moodle-SpellChecker-Path-Authenticated-Remote-Command-Execution.html
https://github.com/moodle/moodle
https://talosintelligence.com/vulnerability_reports/TALOS-2021-1277
CVE-2021-21809 https://nvd.nist.gov/vuln/detail/CVE-2021-21809
Data source Metasploit
Description Moodle allows an authenticated administrator to define spellcheck settings via the web interface. An administrator can update the aspell path to include a command injection. This is extremely similar to CVE-2013-3630, just using a different variable. This module was tested against Moodle version 3.11.2, 3.10.0, and 3.8.0.
Note 
Stability:
  - crash-safe
Reliability:
  - repeatable-session
SideEffects:
  - config-changes
  - ioc-in-logs
Ransomware campaign use Unknown
Source publication date June 22, 2021
Platform PHP
Source URL https://github.com/rapid7/metasploit-framework/tree/master/modules/exploits/multi/http/moodle_spelling_path_rce.rb

No EPSS data available for this advisory.

Patch URL
There are no known patches.
Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H Found at https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2022/05/GHSA-c7jj-vfmr-j9mj/GHSA-c7jj-vfmr-j9mj.json
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none

There are no SSVC decisions available.