CVE-2021-20186
CVE-2021-20186 is a medium-severity vulnerability in Moodle with a CVSS 3.x base score of 5.4. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-79.
Key facts
- Severity: Medium (CVSS 3.x base score 5.4)
- CVSS v2: 2.1
- EPSS exploit prediction: 1% (51st percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-79
- Affected product: Moodle
- Published:
- Last modified:
Description
It was found in Moodle before version 3.10.1, 3.9.4, 3.8.7 and 3.5.16 that if the TeX notation filter was enabled, additional sanitizing of TeX content was required to prevent the risk of stored XSS.
Frequently asked questions
- What is CVE-2021-20186?
- It was found in Moodle before version 3.10.1, 3.9.4, 3.8.7 and 3.5.16 that if the TeX notation filter was enabled, additional sanitizing of TeX content was required to prevent the risk of stored XSS.
- How severe is CVE-2021-20186?
- CVE-2021-20186 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
- Is CVE-2021-20186 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-20186?
- CVE-2021-20186 affects Moodle. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-20186?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2021-20186 published?
- CVE-2021-20186 was published on 2021-01-28 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:a:moodle:moodle:*:*:*:*:*:*:*:*
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