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Fencer Intel
critical 9.8

CVE-2026-18431 json

Avada <= 7.16 and Fusion Builder <= 3.16 - Unauthenticated Remote Code Execution via Arbitrary File Write

published 2mo ago modified 2mo ago also EUVD-2026-66293

cvss
9.8
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.9%
EPSS 0.9% chance of exploitation in 30 days, percentile 59%
public exploits
0
none known

Summary

The Avada theme for WordPress is vulnerable to Arbitrary File Write in all versions up to, and including, 7.16 when the Fusion Builder plugin is installed and active in versions up to, and including, 3.16. This is due to a chain of authorization and input validation weaknesses across the two components that makes it possible for unauthenticated attackers to write attacker-controlled files to the server. This can be used to create and execute arbitrary PHP files, resulting in remote code execution and complete site compromise. Successful exploitation requires both Avada and Fusion Builder to be installed and active, as well as certain administrator-authored content to be present.

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CISA SSVC

Exploitation
none
Automatable
yes
Technical impact
total
Assessed
2mo ago

Exploit prediction

0.90% chance of exploitation in the next 30 days, higher than 59% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
CNA 3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

  • themefusion Avada (Fusion) Builder
  • ThemeFusion Avada | Website Builder For WordPress & WooCommerce

Classification

Weakness
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.