#VU54977 SQL injection in Moodle - CVE-2021-36393

Vulnerability identifier: #VU54977

Vulnerability risk: High

CVSSv4.0: 7.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:P/U:Amber]

CVE-ID: CVE-2021-36393

CWE-ID: CWE-89

Exploitation vector: Network

Exploit availability: Yes

Vulnerable software:
Moodle
Web applications / Other software

Vendor: moodle.org

Description

The vulnerability allows a remote user to execute arbitrary SQL queries in database.

The vulnerability exists due to insufficient sanitization of user-supplied data in the library fetching a user's recent courses. A remote user can send a specially crafted request to the affected application and execute arbitrary SQL commands within the application database.

Successful exploitation of this vulnerability may allow a remote attacker to read, delete, modify data in database and gain complete control over the affected application.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Moodle: 3.9.0 - 3.9.7, 3.10.0 - 3.11.0

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External links
https://moodle.org/mod/forum/discuss.php?d=424798
https://git.moodle.org/gw?p=moodle.git&a=search&h=HEAD&st=commit&s=MDL-71242
https://tracker.moodle.org/browse/MDL-71242
https://github.com/T0X1Cx/CVE-2021-36393-Exploit

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability. However, proof of concept for this vulnerability is available.