5.4
MEDIUM
CVE-2021-27131
Moodle XSS Injection Vulnerability
Description

Moodle 3.10.1 is vulnerable to persistent/stored cross-site scripting (XSS) due to the improper input sanitization on the "Additional HTML Section" via "Header and Footer" parameter in /admin/settings.php. This vulnerability is leading an attacker to steal admin and all user account cookies by storing the malicious XSS payload in Header and Footer. NOTE: this is disputed by the vendor because the "Additional HTML Section" for "Header and Footer" can only be supplied by an administrator, who is intentionally allowed to enter unsanitized input (e.g., site-specific JavaScript).

INFO

Published Date :

May 16, 2023, 8:15 p.m.

Last Modified :

Aug. 3, 2024, 9:15 p.m.

Remotely Exploitable :

Yes !

Impact Score :

2.7

Exploitability Score :

2.3
Affected Products

The following products are affected by CVE-2021-27131 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Moodle moodle
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2021-27131.

URL Resource
https://docs.moodle.org/402/en/Risks
https://github.com/moodle/moodle Product
https://github.com/p4nk4jv/CVEs-Assigned/blob/master/Moodle-3.10.1-CVE-2021-27131.md Exploit

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2021-27131 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2021-27131 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by [email protected]

    Aug. 03, 2024

    Action Type Old Value New Value
  • CVE Modified by [email protected]

    May. 17, 2024

    Action Type Old Value New Value
  • CVE Modified by [email protected]

    May. 14, 2024

    Action Type Old Value New Value
  • CVE Modified by [email protected]

    Apr. 11, 2024

    Action Type Old Value New Value
  • CVE Modified by [email protected]

    Mar. 21, 2024

    Action Type Old Value New Value
    Added Tag MITRE disputed
  • CVE Modified by [email protected]

    Nov. 07, 2023

    Action Type Old Value New Value
    Changed Description ** DISPUTED ** Moodle 3.10.1 is vulnerable to persistent/stored cross-site scripting (XSS) due to the improper input sanitization on the "Additional HTML Section" via "Header and Footer" parameter in /admin/settings.php. This vulnerability is leading an attacker to steal admin and all user account cookies by storing the malicious XSS payload in Header and Footer. NOTE: this is disputed by the vendor because the "Additional HTML Section" for "Header and Footer" can only be supplied by an administrator, who is intentionally allowed to enter unsanitized input (e.g., site-specific JavaScript). Moodle 3.10.1 is vulnerable to persistent/stored cross-site scripting (XSS) due to the improper input sanitization on the "Additional HTML Section" via "Header and Footer" parameter in /admin/settings.php. This vulnerability is leading an attacker to steal admin and all user account cookies by storing the malicious XSS payload in Header and Footer. NOTE: this is disputed by the vendor because the "Additional HTML Section" for "Header and Footer" can only be supplied by an administrator, who is intentionally allowed to enter unsanitized input (e.g., site-specific JavaScript).
  • CVE Modified by [email protected]

    Jun. 14, 2023

    Action Type Old Value New Value
    Changed Description Moodle 3.10.1 is vulnerable to persistent/stored cross-site scripting (XSS) due to the improper input sanitization on the "Additional HTML Section" via "Header and Footer" parameter in /admin/settings.php. This vulnerability is leading an attacker to steal admin and all user account cookies by storing the malicious XSS payload in Header and Footer. ** DISPUTED ** Moodle 3.10.1 is vulnerable to persistent/stored cross-site scripting (XSS) due to the improper input sanitization on the "Additional HTML Section" via "Header and Footer" parameter in /admin/settings.php. This vulnerability is leading an attacker to steal admin and all user account cookies by storing the malicious XSS payload in Header and Footer. NOTE: this is disputed by the vendor because the "Additional HTML Section" for "Header and Footer" can only be supplied by an administrator, who is intentionally allowed to enter unsanitized input (e.g., site-specific JavaScript).
    Added Reference https://docs.moodle.org/402/en/Risks [No Types Assigned]
  • Initial Analysis by [email protected]

    May. 25, 2023

    Action Type Old Value New Value
    Added CVSS V3.1 NIST AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
    Changed Reference Type https://github.com/moodle/moodle No Types Assigned https://github.com/moodle/moodle Product
    Changed Reference Type https://github.com/p4nk4jv/CVEs-Assigned/blob/master/Moodle-3.10.1-CVE-2021-27131.md No Types Assigned https://github.com/p4nk4jv/CVEs-Assigned/blob/master/Moodle-3.10.1-CVE-2021-27131.md Exploit
    Added CWE NIST CWE-79
    Added CPE Configuration OR *cpe:2.3:a:moodle:moodle:3.10.1:*:*:*:*:*:*:*
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2021-27131 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2021-27131 weaknesses.

Exploit Prediction

EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.

0.07 }} 0.01%

score

0.28768

percentile

CVSS31 - Vulnerability Scoring System
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality
Integrity
Availability