Multiple vulnerabilities in Moodle

1) Input validation error

EUVDB-ID: #VU54987

Risk: Low

CVSSv4.0: 0.5 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-36403

CWE-ID: CWE-20 - Improper input validation

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform phishing attack.

The vulnerability exists due to insufficient validation of user-supplied input when processing email notifications containing HTML. In some circumstances, email notifications of messages could have the link back to the original message hidden by HTML, which may pose a phishing risk.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Moodle: 3.9.0 - 3.11.0

CPE2.3

External links

https://moodle.org/mod/forum/discuss.php?d=424809
https://git.moodle.org/gw?p=moodle.git&a=search&h=HEAD&st=commit&s=MDL-71919
https://tracker.moodle.org/browse/MDL-71919

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) Input validation error

EUVDB-ID: #VU54986

Risk: Low

CVSSv4.0: 0.5 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-36402

CWE-ID: CWE-20 - Improper input validation

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform phishing attacks.

The vulnerability exists due to insufficient validation of user-supplied input when processing user names in account confirmation emails. A remote attacker can modify email contents via a specially crafted username and perform phishing attack.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Moodle: 3.9.0 - 3.11.0

CPE2.3

External links

https://moodle.org/mod/forum/discuss.php?d=424808
https://git.moodle.org/gw?p=moodle.git&a=search&h=HEAD&st=commit&s=MDL-58393
https://tracker.moodle.org/browse/MDL-58393

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.

3) Stored cross-site scripting

EUVDB-ID: #VU54985

Risk: Medium

CVSSv4.0: 1.2 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-36401

CWE-ID: CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Exploit availability: No

Description

The disclosed vulnerability allows a remote user to perform cross-site scripting (XSS) attacks.

The vulnerability exists due to insufficient sanitization of user-supplied input when exporting to data formats supporting HTML. A remote user can inject and execute arbitrary HTML and script code in user's browser in context of vulnerable website.

Successful exploitation of this vulnerability may allow a remote attacker to steal potentially sensitive information, change appearance of the web page, perform phishing and drive-by-download attacks.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Moodle: 3.9.0 - 3.11.0

CPE2.3

External links

https://moodle.org/mod/forum/discuss.php?d=424807
https://git.moodle.org/gw?p=moodle.git&a=search&h=HEAD&st=commit&s=MDL-71981
https://tracker.moodle.org/browse/MDL-71981

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.

4) Externally Controlled Reference to a Resource in Another Sphere

EUVDB-ID: #VU54984

Risk: Low

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

CVE-ID: CVE-2021-36400

CWE-ID: CWE-610 - Externally Controlled Reference to a Resource in Another Sphere

Exploit availability: No

Description

The vulnerability allows a remote attacker to bypass implemented security restrictions.

The vulnerability exists due to incorrect permissions checks when deleting calendar URLs. A remote user can delete calendar URLs that belong to other application users.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Moodle: 3.9.0 - 3.11.0

CPE2.3

External links

https://moodle.org/mod/forum/discuss.php?d=424806
https://git.moodle.org/gw?p=moodle.git&a=search&h=HEAD&st=commit&s=MDL-71978
https://tracker.moodle.org/browse/MDL-71978

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.

5) Stored cross-site scripting

EUVDB-ID: #VU54983

Risk: Low

CVSSv4.0: 0.5 [CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-36399

CWE-ID: CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Exploit availability: No

Description

The disclosed vulnerability allows a remote user to perform cross-site scripting (XSS) attacks.

The vulnerability exists due to insufficient sanitization of user-supplied data passed via the user ID number to quiz override screens. A remote user can inject and execute arbitrary HTML and script code in user's browser in context of vulnerable website.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Moodle: 3.11 - 3.11.0

CPE2.3

External links

https://moodle.org/mod/forum/discuss.php?d=424805
https://git.moodle.org/gw?p=moodle.git&a=search&h=HEAD&st=commit&s=MDL-71898
https://tracker.moodle.org/browse/MDL-71898

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.

6) Stored cross-site scripting

EUVDB-ID: #VU54982

Risk: Low

CVSSv4.0: 0.5 [CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-36398

CWE-ID: CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Exploit availability: No

Description

The disclosed vulnerability allows a remote user to perform cross-site scripting (XSS) attacks.

The vulnerability exists due to insufficient sanitization of user-supplied data passed via the user ID number to the web service token list. A remote user can inject and execute arbitrary HTML and script code in user's browser in context of vulnerable website.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Moodle: 3.11 - 3.11.0

CPE2.3

External links

https://moodle.org/mod/forum/discuss.php?d=424804
https://git.moodle.org/gw?p=moodle.git&a=search&h=HEAD&st=commit&s=MDL-71760
https://tracker.moodle.org/browse/MDL-71760

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.

7) Externally Controlled Reference to a Resource in Another Sphere

EUVDB-ID: #VU54981

Risk: Low

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

CVE-ID: CVE-2021-36397

CWE-ID: CWE-610 - Externally Controlled Reference to a Resource in Another Sphere

Exploit availability: No

Description

The vulnerability allows a remote user to bypass implemented security restrictions.

The vulnerability exists due to insufficient permissions checks when deleting messages. A remote user can delete messages that belong to other web application users.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Moodle: 3.9.0 - 3.11.0

CPE2.3

External links

https://moodle.org/mod/forum/discuss.php?d=424803
https://git.moodle.org/gw?p=moodle.git&a=search&h=HEAD&st=commit&s=MDL-71917
https://tracker.moodle.org/browse/MDL-71917

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.

8) Blind server-side request forgery (SSRF)

EUVDB-ID: #VU54980

Risk: Medium

CVSSv4.0: 5.5 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:L/SI:N/SA:N/E:P/U:Green]

CVE-ID: CVE-2021-36396

CWE-ID: CWE-918 - Server-Side Request Forgery (SSRF)

Exploit availability: Yes

Description

The disclosed vulnerability allows a remote attacker to perform SSRF attacks.

The vulnerability exists due to insufficient validation of user-supplied input. A remote attacker can bypass cURL blocked hosts/allowed ports restrictions and trick the application to initiate requests to arbitrary systems.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Moodle: 3.9.0 - 3.11.0

CPE2.3

External links

https://moodle.org/mod/forum/discuss.php?d=424802
https://git.moodle.org/gw?p=moodle.git&a=search&h=HEAD&st=commit&s=MDL-71916
https://tracker.moodle.org/browse/MDL-71916

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.

9) Uncontrolled Recursion

EUVDB-ID: #VU54979

Risk: Low

CVSSv4.0: 1.2 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-36395

CWE-ID: CWE-674 - Uncontrolled Recursion

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to improper handling of file repository URLs. A remote attacker can create a specially crafted file repository URL and perform a denial of service attack.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Moodle: 3.9.0 - 3.11.0

CPE2.3

External links

https://moodle.org/mod/forum/discuss.php?d=424801
https://git.moodle.org/gw?p=moodle.git&a=search&h=HEAD&st=commit&s=MDL-71922
https://tracker.moodle.org/browse/MDL-71922

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.

10) Code Injection

EUVDB-ID: #VU54978

Risk: High

CVSSv4.0: 8.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P/U:Amber]

CVE-ID: CVE-2021-36394

CWE-ID: CWE-94 - Improper Control of Generation of Code ('Code Injection')

Exploit availability: Yes

Description

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to improper input validation in Shibboleth authentication plugin. A remote attacker can send a specially crafted request and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Moodle: 3.9.0 - 3.11.0

CPE2.3

External links

https://moodle.org/mod/forum/discuss.php?d=424799
https://git.moodle.org/gw?p=moodle.git&a=search&h=HEAD&st=commit&s=MDL-71957
https://tracker.moodle.org/browse/MDL-71957

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.

11) SQL injection

EUVDB-ID: #VU54977

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 - Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection')

Exploit availability: Yes

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 - 3.11.0

CPE2.3

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

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.

12) SQL injection

EUVDB-ID: #VU54976

Risk: High

CVSSv4.0: 6.2 [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:U/U:Amber]

CVE-ID: CVE-2021-36392

CWE-ID: CWE-89 - Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection')

Exploit availability: No

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 when fetching enrolled 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 - 3.11.0

CPE2.3

External links

https://moodle.org/mod/forum/discuss.php?d=424797
https://tracker.moodle.org/browse/MDL-71241
https://git.moodle.org/gw?p=moodle.git&a=search&h=HEAD&st=commit&s=MDL-71241

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.

Risk	High
Patch available	YES
Number of vulnerabilities	12
CVE-ID	CVE-2021-36403 CVE-2021-36402 CVE-2021-36401 CVE-2021-36400 CVE-2021-36399 CVE-2021-36398 CVE-2021-36397 CVE-2021-36396 CVE-2021-36395 CVE-2021-36394 CVE-2021-36393 CVE-2021-36392
CWE-ID	CWE-20 CWE-79 CWE-610 CWE-918 CWE-674 CWE-94 CWE-89
Exploitation vector	Network
Public exploit	Public exploit code for vulnerability #8 is available. Public exploit code for vulnerability #10 is available. Public exploit code for vulnerability #11 is available.
Vulnerable software	Moodle Web applications / Other software
Vendor	moodle.org