CVE-2026-59835

Published Jul 14, 2026 CVSS 3.1 · 7.7 High EPSS < 1% KEV · Not listed
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.

Analysis

AI-generated

Technical impact

Fortinet FortiSandbox versions 4.4.3 through 4.4.8 and 5.0.0 through 5.0.2 contain a misconfiguration that exposes the VNC service of sandbox virtual machines to unauthenticated network requests. This flaw allows an attacker to connect to the VNC session and view or control the sandbox VM, providing access to the internal sandbox environment without needing credentials. The vulnerability is an instance of CWE‑668, improper access control of resources.

Affected Systems

Affected vendor: Fortinet. Product: FortiSandbox. Affected versions: 4.4.3‑4.4.8 and 5.0.0‑5.0.2.

Risk and Exploitability

The CVSS score is 7.7, indicating high severity, while the EPSS score is under 1 % and the vulnerability is not listed in CISA’s KEV catalog, suggesting that exploitation is unlikely to be widespread at present. An attacker can exploit the flaw from any network‑connected system by sending unauthenticated requests to the exposed VNC port, and the attack can be performed over the network with no authentication required.

Remediation

Vendor Solution

Upgrade to FortiSandbox version 5.0.3 or above Upgrade to FortiSandbox version 4.4.9 or above


OpenCVE Recommended Actions

  • Upgrade FortiSandbox to version 5.0.3 or newer, or to 4.4.9 or newer if using earlier releases.
  • Disable or restrict external VNC access on sandbox VMs until the upgrade is complete.
  • Apply network segmentation or firewall rules to block unauthenticated traffic to the VNC port from untrusted networks.

Generated by OpenCVE AI on August 1, 2026 at 09:59 UTC.

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
Title Unauthenticated VNC Access in FortiSandbox Allowing Remote Desktop
Type Values Removed Values Added
Title Unauthenticated VNC Access in FortiSandbox Allowing Remote Desktop
Type Values Removed Values Added
Title Unauthenticated VNC Access in FortiSandbox
Type Values Removed Values Added
Title Unauthenticated VNC Access in FortiSandbox
Type Values Removed Values Added
Title Unauthenticated VNC Server Access via Resource Exposure in FortiSandbox
Type Values Removed Values Added
Title Unauthenticated VNC Server Access via Resource Exposure in FortiSandbox
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
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.
First Time appeared Fortinet
Fortinet fortisandbox
Weaknesses CWE-668
CPEs cpe:2.3:a:fortinet:fortisandbox:4.4.3:*:*:*:*:*:*:*
cpe:2.3:a:fortinet:fortisandbox:4.4.4:*:*:*:*:*:*:*
cpe:2.3:a:fortinet:fortisandbox:4.4.5:*:*:*:*:*:*:*
cpe:2.3:a:fortinet:fortisandbox:4.4.6:*:*:*:*:*:*:*
cpe:2.3:a:fortinet:fortisandbox:4.4.7:*:*:*:*:*:*:*
cpe:2.3:a:fortinet:fortisandbox:4.4.8:*:*:*:*:*:*:*
cpe:2.3:a:fortinet:fortisandbox:5.0.0:*:*:*:*:*:*:*
cpe:2.3:a:fortinet:fortisandbox:5.0.1:*:*:*:*:*:*:*
cpe:2.3:a:fortinet:fortisandbox:5.0.2:*:*:*:*:*:*:*
Vendors & Products Fortinet
Fortinet fortisandbox
References
Metrics cvssV3_1

{'score': 7.7, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:L/E:P/RL:O/RC:C'}

Weaknesses
  • CWE-668

    Exposure of Resource to Wrong Sphere

Sources

Status
PUBLISHED
Assigner
fortinet
Published
Updated
Jul 16, 2026, 7:35 AM
Reserved
Jul 7, 2026, 3:21 PM
Status
Analyzed
Published
Jul 14, 2026, 4:17 PM
Modified
Oct 24, 2026, 9:10 PM