Threat intelligence

Contact Form by Supsystic <= 1.7.36 - Unauthenticated Server-Side Template Injection via Prefill Functionality

CVE-2026-4257 · contact-form-by-supsystic

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

Vulnerability: Contact Form by Supsystic <= 1.7.36 - Unauthenticated Server-Side Template Injection via Prefill Functionality
Affected software: contact-form-by-supsystic(Plugin)
Affected versions: ≤ 1.7.36
Authentication: Unauthenticated
Vulnerability type: Other
CVE: CVE-2026-4257
Published: 30 March 2026
CISA KEV: Not listed in CISA KEV at last catalog refresh
Impact: This advisory describes a other issue in the affected software. Review the source advisory and your installed version to assess exposure.
Source: Data imported from Wordfence Intelligence (advisory 415c9658-bfb2-453b-a697-c63c08b0ca61). Methodology and redistribution notes

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