CVE-2026-4257
Unauthenticated SSTI leads to RCE in Supsystic Contact Form for WordPress (<=1.7.36).
Is CVE-2026-4257 being exploited?
Not confirmed. CVE-2026-4257 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 41% probability of exploitation in the next 30 days.
How severe is CVE-2026-4257?
CVE-2026-4257 is rated Critical with a CVSS score of 9.8. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-4257?
Yes. A fix has been recorded for CVE-2026-4257. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-4257 affect?
CVE-2026-4257 affects WordPress sites using Contact Form by Supsystic (<=1.7.36), Web servers hosting affected plugin. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-4257?
Upgrade to 1.7.37+ or remove plugin
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
RCE via unauthenticated Twig SSTI; attacker can execute PHP functions and OS commands on the server.
Immediate action required
- affected<= 1.7.36
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.