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Fencer Intel
medium 5.3

CVE-2026-15239 json

Simple CAPTCHA with Cloudflare Turnstile < 1.42.0 - Unauthenticated Turnstile Protection Bypass via Reusable Forminator Cache Key

published 3mo ago modified 2mo ago also EUVD-2026-54401

cvss
5.3
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 4%
public exploits
0
none known

Summary

The Simple CAPTCHA with Cloudflare Turnstile WordPress plugin before 1.42.0 does not bind its Turnstile validation cache to the single-use challenge token in its Forminator integration, instead keying it to an attacker-controlled, reusable request value, allowing unauthenticated attackers to solve one challenge and then replay token-less form submissions for a short window, defeating the anti-abuse protection the plugin provides.

Patch / fix

  • Unknown Simple CAPTCHA with Cloudflare Turnstile 1.42.0

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CISA SSVC

Exploitation
Proof of concept is public
Automatable
yes
Technical impact
partial
Assessed
3mo ago

Exploit prediction

0.16% chance of exploitation in the next 30 days, higher than 4% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • wpscan.com https://wpscan.com/vulnerability/28d3bda2-501c-4eeb-9184-c343367adbea/ referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

Affected products

  • Unknown Simple CAPTCHA with Cloudflare Turnstile

Classification

Weakness
  • CWE-345 Insufficient Verification of Data Authenticity
Technology feeds

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.