Multiple vulnerabilities in Moodle

Published: 2021-09-21

Risk	Medium
Patch available	YES
Number of vulnerabilities	5
CVE-ID	CVE-2021-40691 CVE-2021-40695 CVE-2021-40694 CVE-2021-40693 CVE-2021-40692
CWE-ID	CWE-384 CWE-200 CWE-287 CWE-264
Exploitation vector	Network
Public exploit	N/A
Vulnerable software	Moodle Web applications / Other software
Vendor	moodle.org

Security Bulletin

This security bulletin contains information about 5 vulnerabilities.

1) Session Fixation

EUVDB-ID: #VU56753

Risk: Medium

CVSSv4.0: 2.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-40691

CWE-ID: CWE-384 - Session Fixation

Exploit availability: No

Description

The vulnerability allows a remote attacker to hijack the target user's session.

The weakness exists due to a session hijack risk in the Shibboleth authentication plugin. A remote attacker can obtain sensitive information on the system.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Moodle: 3.9.0 - 3.11.2

CPE2.3

External links

https://moodle.org/mod/forum/discuss.php?d=427103

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

2) Information disclosure

EUVDB-ID: #VU56757

Risk: Medium

CVSSv4.0: 4.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-40695

CWE-ID: CWE-200 - Information exposure

Exploit availability: No

Description

The vulnerability allows a remote attacker to gain access to potentially sensitive information.

The vulnerability exists due to excessive data output by the application. A remote authenticated attacker can view their quiz grade before it had been released, using a quiz web service.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Moodle: 3.9.0 - 3.11.2

CPE2.3

External links

https://moodle.org/mod/forum/discuss.php?d=427107

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.

3) Information disclosure

EUVDB-ID: #VU56756

Risk: Low

CVSSv4.0: 4.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-40694

CWE-ID: CWE-200 - Information exposure

Exploit availability: No

Description

The vulnerability allows a remote user to gain access to potentially sensitive information.

The vulnerability exists due to insufficient escaping of the LaTeX preamble. A remote administrator can read files available to the HTTP server system account.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Moodle: 3.9.0 - 3.11.2

CPE2.3

External links

https://moodle.org/mod/forum/discuss.php?d=427106

Q & A

Can this vulnerability be exploited remotely?

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

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

4) Improper Authentication

EUVDB-ID: #VU56755

Risk: Medium

CVSSv4.0: 2.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-40693

CWE-ID: CWE-287 - Improper Authentication

Exploit availability: No

Description

The vulnerability allows a remote attacker to bypass authentication process.

The vulnerability exists due to a type juggling issue in the external database authentication functionality. A remote attacker can bypass authentication process and gain unauthorized access to the application.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Moodle: 3.9.0 - 3.11.2

CPE2.3

External links

https://moodle.org/mod/forum/discuss.php?d=427105

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

5) Permissions, Privileges, and Access Controls

EUVDB-ID: #VU56754

Risk: Medium

CVSSv4.0: 1.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-40692

CWE-ID: CWE-264 - Permissions, Privileges, and Access Controls

Exploit availability: No

Description

The vulnerability allows a remote attacker to escalate privileges on the system.

The vulnerability exists due to insufficient capability checks. A remote authenticated attacker can download users outside of their courses.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Moodle: 3.9.0 - 3.11.2

CPE2.3

External links

https://moodle.org/mod/forum/discuss.php?d=427104

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.