4.8

CVE-2026-58034: mediawiki Cross-site Scripting

CVSS: 4.8v3.1MediumAnalyzed
Published 01-07-2026Last modified 01-07-2026
Open JSON

Vulnerability summary

CVE-2026-58034 is a medium (CVSS 4.8) Cross-site Scripting vulnerability in mediawiki. EPSS estimates a 0.29% chance of exploitation in the next 30 days, higher than 20% of scored vulnerabilities.

Overall risk
19/100
0100
Low · default modelHow is this calculated?
CVSS score
4.8/10
010
Medium · v3.1 (NVD)
EPSS score
0.29%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 01-07-2026
    PublishedVulnerability first disclosed.
  2. 01-07-2026
    Last modifiedVulnerability information updated.

Description

Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in Wikimedia Foundation CheckUser. This vulnerability is associated with program files modules/ext.CheckUser.TempAccounts/components/blockConnectedTempAccountsField.Vue. This issue affects CheckUser: from 1.46.0-rc.0 before 1.46.0.

CVSS metrics

3 scores · 2 sources · 2 versions

EPSS trend

Probability

0.29%

Chance of exploitation in the next 30 days

Percentile

20%

Versus all other CVEs

30-day change

0.00 pp

From 0.29% on 21-09-2026

21-09-202621-10-2026
EPSS score
0.29%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Mediawiki1 product
Wikimedia foundation1 product

2 vendors · 2 products

References

1 links