Threat intelligence

SmartSMTP <= 1.2.0 - Unauthenticated Stored Cross-Site Scripting

CVE-2026-66606 · smart-smtp

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

Vulnerability: SmartSMTP <= 1.2.0 - Unauthenticated Stored Cross-Site Scripting
Affected software: smart-smtp(Plugin)
Affected versions: ≤ 1.2.0
Authentication: Unauthenticated
Vulnerability type: Cross-site scripting
CVE: CVE-2026-66606
Published: 19 August 2026
CISA KEV: Not listed in CISA KEV at last catalog refresh
Impact: May allow attackers to run scripts in visitors' browsers or hijack admin sessions.
Source: Data imported from Wordfence Intelligence (advisory 1ed34888-ae77-4e48-9c2d-de3202fb2eb7). Methodology and redistribution notes

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