Mailster WordPress Newsletter Plugin vulnerabilities
Plugin slug mailster · 6 known vulnerabilities · latest disclosed 2026-07-22 · WordPress.org page
Every listed vulnerability has a fix. Version 4.1.18 or later is not affected by any of them. If your site runs an older version, update it.
3 of 6 rated high or critical (CVSS 7 or more).
Known vulnerabilities in Mailster WordPress Newsletter Plugin
| Severity | Affected versions | Fixed in | CVE | Published | Details |
|---|---|---|---|---|---|
| High 7.2 | <= 4.1.17 | 4.1.18 | CVE-2026-27064 | 2026-07-22 | Advisory |
| Medium 6.1 | < 4.1.14 | 4.1.14 | CVE-2025-64203 | 2025-10-27 | Advisory |
| Medium 6.1 | <= 4.0.9 | 4.0.10 | CVE-2024-37433 | 2024-06-28 | Advisory |
| Critical 9.8 | <= 4.0.6 | 4.0.7 | CVE-2024-32523 | 2024-04-15 | Advisory |
| Medium 6.1 | <= 1.0.3 | 2.0.0 | CVE-2024-30503 | 2024-03-28 | Advisory |
| High 7.2 | <= 2.4.5.1 | 2.4.9 | none | 2020-10-14 | Advisory |
Check if a site is affected
Enter a site address to see which version of Mailster WordPress Newsletter Plugin and other plugins it runs, and whether they match a known vulnerability.
Questions
Is the Mailster WordPress Newsletter Plugin plugin safe to use?
All 6 known issues are fixed in current versions (4.1.18 or later). Keeping it updated is what matters.
How do I check which version of Mailster WordPress Newsletter Plugin my site runs?
In WordPress go to Plugins > Installed Plugins. From the outside, the free PluginPeek scan below reads the version from the site's public files.
How do I fix a vulnerable plugin?
Make a full backup, then update it from Dashboard > Updates and check the site afterwards. If you would rather not, we can do it for a fixed $99, paid after you have checked the site.