CVE-2021-27131

Public Exploit

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).

Category

5.4
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.12%
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://github.com/moodle/moodle product
https://github.com/p4nk4jv/CVEs-Assigned/blob/master/Moodle-3.10.1-CVE-2021-27131.md exploit
https://docs.moodle.org/402/en/Risks

Frequently Asked Questions

What is the severity of CVE-2021-27131?
CVE-2021-27131 has been scored as a medium severity vulnerability.
How to fix CVE-2021-27131?
To fix CVE-2021-27131, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-27131 being actively exploited in the wild?
It is possible that CVE-2021-27131 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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