Vulnerability · Published Jul 1, 2026 · Assigned by wikimedia-foundation

CVE-2026-58034Stored XSS through a system message when blocking a temporary account that's related to other temporary accounts

None 0.0

In plain English

A cross-site scripting in CheckUser from Wikimedia Foundation. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 21% of all known vulnerabilities).

Severity (CVSS 4.0)0.0None

Exploit odds (30 days)0.3%top 78.7% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official 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.

Affected products (as reported)

Vendor	Product	Versions
Wikimedia Foundation	CheckUser	1.46.0-rc.0 – before 1.46.0

Weakness: CWE-79 · Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:A/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N

References

https://phabricator.wikimedia.org/T428820