CVE-2021-25038: Multisite User Sync/Unsync < 2.1.2 - Reflected Cross-Site Scripting

Severity: medium (CVSS 6.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.8% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2022-03-07 · updated 2026-06-17
Weakness: CWE-79

Description

The WordPress Multisite User Sync/Unsync WordPress plugin before 2.1.2 does not sanitise and escape the wmus_source_blog and wmus_record_per_page parameters before outputting them back in attributes, leading to Reflected Cross-Site Scripting issues

Affected products

WordPress Multisite User Sync/Unsync: before 2.1.2 — fixed in 2.1.2

How to fix

Upgrade to a fixed version: WordPress Multisite User Sync/Unsync 2.1.2. Check the vendor advisory for mitigations.

References

https://wpscan.com/vulnerability/72ccdcb9-3d24-41d7-b9fa-c8bd73d30aa6
https://wpscan.com/vulnerability/72ccdcb9-3d24-41d7-b9fa-c8bd73d30aa6

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