Critical FortiSandbox API Flaws Enable Unauthenticated Command Execution
Fortinet disclosed two critical vulnerabilities in FortiSandbox that allow remote, unauthenticated attackers to compromise exposed appliances through crafted HTTP requests. CVE-2026-39808 is an OS command injection flaw in the FortiSandbox API that can lead to unauthorized command or code execution, while CVE-2026-39813 is a path traversal issue in the JRPC API that can bypass authentication and enable privilege escalation. Both issues carry a CVSS v3 score of 9.1.
The flaws affect FortiSandbox 4.4.0 through 4.4.8, and CVE-2026-39813 also impacts 5.0.0 through 5.0.5. Fortinet released fixes in 4.4.9 for both vulnerabilities and 5.0.6 for the JRPC issue, and said it had not observed exploitation in the wild at the time of disclosure. Organizations were urged to patch immediately, review internet-exposed deployments, and restrict API access to trusted networks until upgrades are completed.
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2 events from the most recent confirmed update back to the earliest known activity.
Fortinet releases fixed FortiSandbox versions and mitigation guidance
Fortinet said CVE-2026-39808 is fixed in FortiSandbox 4.4.9, while CVE-2026-39813 is fixed in versions 4.4.9 and 5.0.6. The company also stated it had not observed exploitation in the wild at disclosure time and urged customers to patch, review exposed deployments, and restrict API access to trusted networks as an interim mitigation.
Fortinet discloses two critical FortiSandbox vulnerabilities
On 2026-04-14, Fortinet disclosed CVE-2026-39808 and CVE-2026-39813, two critical FortiSandbox flaws rated CVSS 9.1 that can be exploited remotely without authentication via crafted HTTP requests. The issues affect FortiSandbox 4.4.x, and CVE-2026-39813 also affects versions 5.0.0 through 5.0.5.
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Fortinet fixes critical FortiSandbox vulnerabilities (CVE-2026-39813, CVE-2026-39808) - Help Net Security
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Open sourceHow to find Fortinet FortiSandbox on your network - runZero
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Open sourceCritical FortiSandbox Vulnerabilities Allow Attackers to Execute Unauthorized Commands
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Fortinet Patches Critical RCE Flaws in FortiAuthenticator and FortiSandbox
Fortinet released fixes for two **critical** vulnerabilities that could let remote, unauthenticated attackers run unauthorized code or commands on exposed systems. The first, **`CVE-2026-44277`**, is an improper access control flaw in **FortiAuthenticator** with a **CVSS 9.1** rating; it affects versions **8.0.0**, **8.0.2**, **6.6.0-6.6.8**, and **6.5.0-6.5.6**, and was patched in **8.0.3**, **6.6.9**, and **6.5.7**. Fortinet said the issue stems from insufficient authorization checks on API endpoints and could allow unauthorized API access, privilege escalation, and command execution, while **FortiAuthenticator Cloud is not affected**. Fortinet also disclosed **`CVE-2026-26083`**, a **CVSS 9.1** missing-authorization flaw in the **FortiSandbox** Web UI that impacts **FortiSandbox**, **FortiSandbox Cloud**, and **FortiSandbox PaaS**, potentially enabling arbitrary code execution across on-premises and cloud deployments. Canada’s Cyber Centre warned that the advisories span multiple Fortinet products and urged administrators to review Fortinet PSIRT notices and apply updates promptly. Public reporting said Fortinet had not observed either flaw being exploited in the wild at disclosure, but the breadth of affected security infrastructure and Fortinet’s history of high-value exploitation have increased urgency around patching exposed appliances.
May 16, 2026
Fortinet Patches Critical FortiSandbox and FortiManager Command-Execution Flaws
Fortinet issued multiple 2026 security advisories covering a broad set of vulnerabilities across **FortiSandbox, FortiManager, FortiAnalyzer, FortiOS, FortiAP, FortiProxy, FortiPAM, FortiSwitchManager, FortiSwitchAXFixed,** and related cloud offerings. The most severe flaws affect **FortiSandbox**, including `CVE-2026-39808`, an unauthenticated OS command injection bug that could allow arbitrary command execution and full device compromise, `CVE-2026-39813`, a path traversal issue in the JRPC API that may enable authentication bypass and privilege escalation, and `CVE-2026-26083`, a missing authorization flaw that can expose restricted functionality and sensitive sandbox analysis data through the GUI without authentication. National cyber authorities in Canada and Belgium separately warned organizations to apply Fortinet’s fixes immediately. Fortinet also disclosed high-risk issues in management platforms, notably `CVE-2025-54820`, a stack-based buffer overflow in the **FortiManager** `fgtupdates` service that can let remote unauthenticated attackers execute unauthorized commands when the service is enabled, as well as a heap-based buffer overflow affecting **FortiAnalyzer Cloud** and **FortiManager Cloud**. Additional weaknesses across the product line include authentication and MFA bypasses, SQL injection, API denial of service, CLI command injection in FortiAP, CAPWAP daemon memory corruption in FortiOS, stored and reflected XSS, improper access control, and credential exposure. Fortinet advised customers to upgrade to fixed releases, disable exposed services such as `fgtupdates` where possible, restrict CLI, SSH, and API access, and monitor logs for anomalous authentication, privilege escalation, and endpoint activity.
Jun 18, 2026
Fortinet Discloses Critical Command Injection and SQL Injection Flaws
Fortinet disclosed two high-severity vulnerabilities affecting **FortiSandbox** and **FortiDDoS-F**, both of which could allow unauthorized code or command execution. **CVE-2026-39808** is an OS command injection flaw in FortiSandbox versions `4.4.0` through `4.4.8`, mapped to `CWE-78`, with a `CVSS 3.1` vector of `AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`, indicating remote exploitation without authentication and high impact across confidentiality, integrity, and availability. Fortinet also disclosed **CVE-2026-39815**, an SQL injection vulnerability in FortiDDoS-F versions `7.2.1` through `7.2.2`, mapped to `CWE-89`. The flaw requires low privileges but may likewise enable unauthorized code or command execution, and carries a `CVSS 3.1` vector of `AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`. The issues are tracked in Fortinet advisories **FG-IR-26-100** and **FG-IR-26-119**, respectively, expanding the vendor's latest set of appliance security fixes.
May 24, 2026