Cyber Resilience

CVE-2023-39008

RCE in Opnsense ≤ 23.7

Public PoCRCECommand Injection
Published
09 August 2023
Modified
21 November 2024
Patch / advisory
View advisory
CVSS Score v3.1 9.8
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.031 87th percentile
Risk Priority 78 floored blend · peak EPSS

Summary

CVE-2023-39008 is a critical-severity Command Injection (CWE-77) vulnerability in Opnsense Opnsense. Its CVSS base score is 9.8 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Command and Scripting Interpreter (T1059); ranked in the top 13% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

A command injection vulnerability tracked as CVE-2023-39008 affects the /api/cron/settings/setJob/ component in OPNsense Community Edition prior to version 23.7 and Business Edition prior to 23.4.2. The flaw, assigned CWE-77 and carrying a CVSS 3.1 score of 9.8, permits unauthenticated remote attackers to supply crafted input that results in execution of arbitrary system commands on the underlying host.

Because the affected endpoint is reachable over the network with no authentication or user interaction required, an attacker can leverage the injection to run commands with the privileges of the OPNsense web-service process, potentially leading to full system compromise including configuration changes, data exfiltration, or persistence.

Public references point to a corrective commit in the OPNsense core repository that addresses the input-handling issue in the cron job settings endpoint; operators are advised to upgrade to the fixed releases. The associated EPSS score remains at 0.0518 with no material increase observed since disclosure.

OWASP Top 10 for Web (2025)

A05:2025 Injection

EU & UK References

Vulnerability Data

A command injection vulnerability in the component /api/cron/settings/setJob/ of OPNsense Community Edition before 23.7 and Business Edition before 23.4.2 allows attackers to execute arbitrary system commands.

CWE(s)
CWE-77

Related Threats

MITRE ATT&CK Enterprise Techniques

T1059 Command and Scripting Interpreter Execution
Adversaries may abuse command and script interpreters to execute commands, scripts, or binaries.
attack.mitre.org →
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
attack.mitre.org →
T1059.001 PowerShell Execution
Adversaries may abuse PowerShell commands and scripts for execution.
attack.mitre.org →
T1059.003 Windows Command Shell Execution
Adversaries may abuse the Windows command shell for execution.
attack.mitre.org →
T1059.004 Unix Shell Execution
Adversaries may abuse Unix shell commands and scripts for execution.
attack.mitre.org →
T1059.008 Network Device CLI Execution
Adversaries may abuse scripting or built-in command line interpreters (CLI) on network devices to execute malicious command and payloads.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2023-39001Same product: Opnsense Opnsense
CVE-2025-50989Same product: Opnsense Opnsense
CVE-2026-44194Same product: Opnsense Opnsense
CVE-2026-45158Same product: Opnsense Opnsense
CVE-2026-44193Same product: Opnsense Opnsense
CVE-2023-38999Same product: Opnsense Opnsense
CVE-2026-30868Same product: Opnsense Opnsense
CVE-2023-38997Same product: Opnsense Opnsense
CVE-2026-34578Same product: Opnsense Opnsense
CVE-2023-39002Same product: Opnsense Opnsense

Affected Assets

opnsense
opnsense
≤ 23.7

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)

—

Validate
Prove the fix (OWASP ASVS)
  • V1.2.3
  • V1.2.5
  • V1.2.8
  • V1.2.9

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly require input validation and neutralization that prevent command injection.

DE.CM-09 partial match
prevents

Runtime monitoring of software and data can detect anomalous command execution resulting from injection.

ID.RA-01 partial match
prevents

Identifying recorded vulnerabilities enables remediation of command-injection flaws before exploitation.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.8.28 Secure coding mostly match
prevents

Secure coding standards require proper escaping and parameterization of commands, directly eliminating CWE-77.

A.8.29 Security testing in development and acceptance mostly match
finds

Security testing in development catches command-injection vulnerabilities before release.

A.8.25 Secure development life cycle partial match
prevents

Secure development life cycle mandates input validation and command construction practices that directly prevent command injection.

A.8.26 Application security requirements partial match
prevents

Application security requirements explicitly call for controls against injection flaws including command injection.

A.8.27 Secure system architecture and engineering principles partial match
prevents

Secure architecture principles reduce the attack surface but do not prescribe the specific neutralization techniques needed.

A.8.31 Separation of development, test and production environments none match
none

Environment separation limits the blast radius of an exploited command injection but does not prevent the flaw itself.

References