CVE-2025-3581: Newsletter < 8.8.5 - Admin+ Stored XSS via Widget

Severity: medium (CVSS 4.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2025-06-09 · updated 2026-06-17
Weakness: CWE-79

Description

The Newsletter WordPress plugin before 8.8.5 does not validate and escape some of its Widget options before outputting them back in a page/post where the block is embed, which could allow high privilege users such as admin to perform Stored Cross-Site Scripting attacks even when the unfiltered_html capability is disallowed (for example in multisite setup).

Affected products

satollo Newsletter – Send awesome emails from WordPress: before 8.8.5 — fixed in 8.8.5

How to fix

Upgrade to a fixed version: satollo Newsletter – Send awesome emails from WordPress 8.8.5. Check the vendor advisory for mitigations.

References

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