9.1Critical

CVE-2026-3418

The System REST API accepts user-supplied file uploads without enforcing sufficient validation on the file type or destination, allowing files to be written to arbitrary server-accessible locations. Exploitation requires authenticated administrative access with publisher privileges. Successful exploitation permits an authenticated publisher to upload files to server-accessible locations. Depending on the deployment environment and how uploaded files are handled, this could lead to the execution of uploaded content, potentially resulting in remote code execution.

What this means for your business

  • An attacker can use it remotely, over a network, with an administrator login, and without anyone at your company clicking anything.
  • FIRST's prediction model gives it a 0.6% chance of attack attempts being seen in the next 30 days, ranking above 45% of all known flaws.

What to do

  1. 1Ask your IT team or provider whether any of your systems use the affected product.
  2. 2If you do, follow the vendor's guidance. No patch reference has been published yet.

Not sure if your company is exposed?

Fastnexa’s certified penetration testers can check whether attackers could use this flaw, or others like it, against your websites, apps and network. The full test is free for our first 10 founding clients until 31 December 2026.

Scoring

CVSS
9.1 (v3.1)
Vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
Weakness
CWE-434
Assigned by
ed10eef1-636d-4fbe-9993-6890dfa878f8

Dates

Published
2026-08-06
Last modified
2026-08-31
Sources
NVD

References