CyberSecBulletin
CVE-2026-59835NVD status: Analyzed

FortiSandbox: Exposure of Resource to Wrong Sphere

CVE-2026-59835 is a high-severity exposure of resource to wrong sphere vulnerability in FortiSandbox from Fortinet, with a CVSS 3.1 base score of 8.6 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected FortiSandbox versions: 5.0.0 through 5.0.2; 4.4.3 through 4.4.8. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.4% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of FortiSandbox you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on fortiguard.fortinet.com for workarounds and exact fixed builds.
  3. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
FortinetFortiSandbox5.0.0 through 5.0.2; 4.4.3 through 4.4.8Not stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
LowLimited modification of data is possible.
Availability
LowPerformance or availability is reduced.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:L. Scored by CNA (fortinet.com).

Official description

A exposure of resource to wrong sphere vulnerability in Fortinet FortiSandbox 5.0.0 through 5.0.2, FortiSandbox 4.4.3 through 4.4.8 may allow an unauthenticated attacker to access the VNC server of VMs performing scanning via network requests.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Exposure of Resource to Wrong Sphere

The product exposes a resource to the wrong control sphere, providing unintended actors with inappropriate access to the resource.

More Exposure of Resource to Wrong Sphere vulnerabilities (CWE-668)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in FortiSandbox

All FortiSandbox vulnerabilities

Recent Exposure of Resource to Wrong Sphere vulnerabilities

Spotted an error? Tell us.