Threat intelligence

Mailster - Email Newsletter Plugin for WordPress <= 4.1.17 - Authenticated (Editor+) Arbitrary File Upload

CVE-2026-27064 · mailster

Important: Seeing this vulnerability listed does not mean your website is affected. Exposure depends on whether you run Mailster at a vulnerable version. How SiteRespond intelligence works

Vulnerability: Mailster - Email Newsletter Plugin for WordPress <= 4.1.17 - Authenticated (Editor+) Arbitrary File Upload
Affected software: mailster(Plugin)
Affected versions: ≤ 4.1.17
Authentication: Authenticated (see advisory title)
Vulnerability type: Remote code execution
CVE: CVE-2026-27064
Published: 22 July 2026
CISA KEV: Not listed in CISA KEV at last catalog refresh
Impact: May allow attackers to run arbitrary code on the server if exploited.
Source: Data imported from Wordfence Intelligence (advisory 97e68562-92b8-43ac-9a8c-778d2b61f889). Methodology and redistribution notes

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