How severe is CVE-2021-41801?

CVE-2021-41801 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-41801 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (62nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-41801?

CVE-2021-41801 affects Mediawiki. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-41801?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-41801 published?

CVE-2021-41801 was published on 2021-10-11 and last updated on 2026-06-17.

CVE-2021-41801

CVE-2021-41801 is a high-severity vulnerability in Mediawiki with a CVSS 3.x base score of 8.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 6.5
EPSS exploit prediction: 1% (62nd percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Mediawiki
Published: 2021-10-11
Last modified: 2026-06-17

Description

The ReplaceText extension through 1.41 for MediaWiki has Incorrect Access Control. When a user is blocked after submitting a replace job, the job is still run, even if it may be run at a later time (due to the job queue backlog)

Frequently asked questions

What is CVE-2021-41801?: The ReplaceText extension through 1.41 for MediaWiki has Incorrect Access Control. When a user is blocked after submitting a replace job, the job is still run, even if it may be run at a later time (due to the job queue backlog)
How severe is CVE-2021-41801?: CVE-2021-41801 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-41801 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (62nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-41801?: CVE-2021-41801 affects Mediawiki. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-41801?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-41801 published?: CVE-2021-41801 was published on 2021-10-11 and last updated on 2026-06-17.

References

Affected products (1)

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

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