How severe is CVE-2021-36131?

CVE-2021-36131 has a CVSS 3.x base score of 4.8, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2021-36131 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (36th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-36131?

CVE-2021-36131 affects Mediawiki. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-36131?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-36131 published?

CVE-2021-36131 was published on 2021-07-02 and last updated on 2026-06-17.

CVE-2021-36131

CVE-2021-36131 is a medium-severity vulnerability in Mediawiki with a CVSS 3.x base score of 4.8. 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 4.8)
CVSS v2: 3.5
EPSS exploit prediction: 0% (36th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Mediawiki
Published: 2021-07-02
Last modified: 2026-06-17

Description

An XSS issue was discovered in the SportsTeams extension in MediaWiki through 1.36. Within several special pages, a privileged user could inject arbitrary HTML and JavaScript within various data fields. The attack could easily propagate across many pages for many users.

Frequently asked questions

What is CVE-2021-36131?: An XSS issue was discovered in the SportsTeams extension in MediaWiki through 1.36. Within several special pages, a privileged user could inject arbitrary HTML and JavaScript within various data fields. The attack could easily propagate across many pages for many users.
How severe is CVE-2021-36131?: CVE-2021-36131 has a CVSS 3.x base score of 4.8, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2021-36131 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (36th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-36131?: CVE-2021-36131 affects Mediawiki. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-36131?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-36131 published?: CVE-2021-36131 was published on 2021-07-02 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:mediawiki:mediawiki:*:*:*:*:*:*:*:*

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