How severe is CVE-2021-30153?

CVE-2021-30153 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2021-30153 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (53rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-30153?

CVE-2021-30153 affects Mediawiki. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-30153?

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

When was CVE-2021-30153 published?

CVE-2021-30153 was published on 2023-04-15 and last updated on 2026-06-17.

CVE-2021-30153

CVE-2021-30153 is a medium-severity vulnerability in Mediawiki with a CVSS 3.x base score of 4.3. 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-668.

Key facts

Severity: Medium (CVSS 3.x base score 4.3)
EPSS exploit prediction: 1% (53rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-668
Affected product: Mediawiki
Published: 2023-04-15
Last modified: 2026-06-17

Description

An issue was discovered in the VisualEditor extension in MediaWiki before 1.31.13, and 1.32.x through 1.35.x before 1.35.2. . When using VisualEditor to edit a MediaWiki user page belonging to an existing, but hidden, user, VisualEditor will disclose that the user exists. (It shouldn't because they are hidden.) This is related to ApiVisualEditor.

Frequently asked questions

What is CVE-2021-30153?: An issue was discovered in the VisualEditor extension in MediaWiki before 1.31.13, and 1.32.x through 1.35.x before 1.35.2. . When using VisualEditor to edit a MediaWiki user page belonging to an existing, but hidden, user, VisualEditor will disclose that the user exists. (It shouldn't because they are hidden.) This is related to ApiVisualEditor.
How severe is CVE-2021-30153?: CVE-2021-30153 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2021-30153 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (53rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-30153?: CVE-2021-30153 affects Mediawiki. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-30153?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-30153 published?: CVE-2021-30153 was published on 2023-04-15 and last updated on 2026-06-17.

References

Affected products (1)

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

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