Skip to content
Fencer Intel
critical 10.0

CVE-2026-4357 json

Embed HTML5 Game <= 1.3 - Unauthenticated Arbitrary File Upload

published 2mo ago modified 2mo ago also EUVD-2026-70038

cvss
10.0
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.5%
EPSS 0.5% chance of exploitation in 30 days, percentile 46%
public exploits
0
none known

Summary

The Embed HTML5 Game WordPress plugin through 1.3 does not properly restrict who can upload files via the plugin, as well as what can be uploaded, making it possible for unauthenticated attackers to upload PHP backdoors on affected sites.

Is CVE-2026-4357 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

Check with Fencer

CISA SSVC

Exploitation
none
Automatable
yes
Technical impact
total
Assessed
2mo ago

Exploit prediction

0.55% chance of exploitation in the next 30 days, higher than 46% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • wpscan.com https://wpscan.com/vulnerability/b364969d-9dac-46ce-83e2-fc0fc2e5f698/ referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 10.0 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H

Affected products

  • Unknown Embed HTML5 Game

Classification

Weakness
  • CWE-434 Unrestricted Upload of File with Dangerous Type
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.