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Fencer Intel
high 8.8

CVE-2026-15965 json

MaxUpload <= 1.4.0 - Unauthenticated Arbitrary File Upload via 'resumableFilename' Parameter

published 2mo ago modified 2mo ago also EUVD-2026-58837

cvss
8.8
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
1.0%
EPSS 1.0% chance of exploitation in 30 days, percentile 63%
public exploits
0
none known

Summary

The MaxUpload – Big File Uploads – Increase Maximum File Upload Size plugin for WordPress is vulnerable to Arbitrary File Upload in all versions up to, and including, 1.4.0 via the handle_upload function. This is due to a filename-validation mismatch in the handle_upload function where extension and MIME checks are applied to the uploaded chunk's filename but not to the final assembled filename derived from the resumableFilename parameter. This makes it possible for unauthenticated attackers to upload files that may be executable, which makes remote code execution possible.

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CISA SSVC

Exploitation
none
Automatable
no
Technical impact
total
Assessed
2mo ago

Exploit prediction

1.03% chance of exploitation in the next 30 days, higher than 63% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
CNA 3.1 8.8 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected products

  • sadathimel MaxUpload – Big File Uploads – Increase Maximum File Upload Size

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.