CVE-2025-53949Network attack vector

Root code execution via unvalidated upload parameter

Published Dec 9, 2025 · Updated Feb 26, 2026

OS command injection in Fortinet FortiSandbox allows remote authenticated users to execute code through crafted HTTP requests. The upload_vdi_file endpoint passes a user-supplied string to a system call without proper validation, enabling execution as root. A valid authenticated session is required, and successful exploitation grants control of the appliance rather than only interrupting service.

CVSS severity8.8
High
EPSS probability17.19%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

OS command injection in Fortinet FortiSandbox allows remote authenticated users to execute code through crafted HTTP requests. The upload_vdi_file endpoint passes a user-supplied string to a system call without proper validation, enabling execution as root. A valid authenticated session is required, and successful exploitation grants control of the appliance rather than only interrupting service.

The record

CVE
CVE-2025-53949
Published
Dec 9, 2025
Updated
Feb 26, 2026
Vendor
Fortinet
Product
FortiSandbox
Classifications
CWE-78, T1059
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Dec 9, 2025CVE publishedPublication date reported by the CVE source.
  2. Feb 26, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=4.2.1 <=4.2.8
  2. Affected versionversion=4.4.0 <=4.4.7
  3. Affected versionversion=5.0.0 <=5.0.2

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Fortinet · FortiSandboxversion=4.2.1 <=4.2.8; version=4.4.0 <=4.4.7; version=5.0.0 <=5.0.2

Published CVSS scores

8.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
7.2Fortinet, Inc.CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-78Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
T1059Command and Scripting Interpreter

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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