How severe is CVE-2021-42047?

CVE-2021-42047 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-2021-42047 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (46th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-42047?

CVE-2021-42047 affects Mediawiki. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-42047?

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

When was CVE-2021-42047 published?

CVE-2021-42047 was published on 2022-09-29 and last updated on 2026-06-17.

CVE-2021-42047

CVE-2021-42047 is a medium-severity vulnerability in Mediawiki 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)
EPSS exploit prediction: 1% (46th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Mediawiki
Published: 2022-09-29
Last modified: 2026-06-17

Description

An issue was discovered in the Growth extension in MediaWiki through 1.36.2. On any Wiki with the Mentor Dashboard feature enabled, users can login with a mentor account and trigger an XSS payload (such as alert) via Growthexperiments-mentor-dashboard-mentee-overview-no-js-fallback.

Frequently asked questions

What is CVE-2021-42047?: An issue was discovered in the Growth extension in MediaWiki through 1.36.2. On any Wiki with the Mentor Dashboard feature enabled, users can login with a mentor account and trigger an XSS payload (such as alert) via Growthexperiments-mentor-dashboard-mentee-overview-no-js-fallback.
How severe is CVE-2021-42047?: CVE-2021-42047 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-2021-42047 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (46th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-42047?: CVE-2021-42047 affects Mediawiki. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-42047?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-42047 published?: CVE-2021-42047 was published on 2022-09-29 and last updated on 2026-06-17.

References

Affected products (1)

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

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