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CRITICAL CWE-862

CVE-2026-18431

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

Themefusion·Avada (Fusion) Builder

9.8/ 10
CVSS 3.1
Critical severity
0.90%
EPSS exploit odds
Chance of exploitation in the next 30 days
Higher than 60% of all CVEs
Not listed
CISA KEV catalog
No confirmed in-the-wild exploitation on CISA's list.
Timeline
Published
Aug 26, 2026
Updated
Aug 27, 2026
First covered
Aug 26, 2026
Latest story
3 months ago

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.

CWE-862Missing Authorization

Attack profile

Attack vectorNetwork
ComplexityLow
PrivilegesNone
User interactionNone
ScopeUnchanged
ConfidentialityHigh
IntegrityHigh
AvailabilityHigh
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

  • Themefusion Avada (Fusion) Builderup to 3.16
  • ThemeFusion Avada | Website Builder For WordPress & WooCommerceup to 7.16

References

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