CVE-2026-45158: CWE-88: Improper Neutralization of Argument Delimiters in a Command ('Argument Injection') in opnsense core
CVE-2026-45158 is a critical vulnerability in OPNsense core versions prior to 26.1.8. It involves improper neutralization of argument delimiters in a command, specifically in the DHCP configuration processing. Unsanitized user input is passed to a shell script, enabling remote code execution as root on the underlying FreeBSD operating system. This vulnerability is fixed in version 26.1.8. The CVSS score is 9.1, indicating a high severity with network attack vector, low attack complexity, and full impact on confidentiality, integrity, and availability.
AI Analysis
Technical Summary
OPNsense core prior to version 26.1.8 contains a command injection vulnerability (CWE-88) due to unsanitized user input being passed to DHCP configuration shell scripts. This allows an attacker with appropriate privileges to execute arbitrary commands as root on the underlying FreeBSD OS. The vulnerability is resolved in version 26.1.8.
Potential Impact
Successful exploitation results in remote code execution with root privileges on the underlying operating system, compromising confidentiality, integrity, and availability of the affected system. This can lead to full system compromise.
Mitigation Recommendations
Upgrade OPNsense core to version 26.1.8 or later, where this vulnerability is fixed. Since the vendor advisory confirms the fix in 26.1.8, applying this official update is the recommended remediation.
CVE-2026-45158: CWE-88: Improper Neutralization of Argument Delimiters in a Command ('Argument Injection') in opnsense core
Description
CVE-2026-45158 is a critical vulnerability in OPNsense core versions prior to 26.1.8. It involves improper neutralization of argument delimiters in a command, specifically in the DHCP configuration processing. Unsanitized user input is passed to a shell script, enabling remote code execution as root on the underlying FreeBSD operating system. This vulnerability is fixed in version 26.1.8. The CVSS score is 9.1, indicating a high severity with network attack vector, low attack complexity, and full impact on confidentiality, integrity, and availability.
CVSS v3.1
Score 9.1critical
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
OPNsense core prior to version 26.1.8 contains a command injection vulnerability (CWE-88) due to unsanitized user input being passed to DHCP configuration shell scripts. This allows an attacker with appropriate privileges to execute arbitrary commands as root on the underlying FreeBSD OS. The vulnerability is resolved in version 26.1.8.
Potential Impact
Successful exploitation results in remote code execution with root privileges on the underlying operating system, compromising confidentiality, integrity, and availability of the affected system. This can lead to full system compromise.
Mitigation Recommendations
Upgrade OPNsense core to version 26.1.8 or later, where this vulnerability is fixed. Since the vendor advisory confirms the fix in 26.1.8, applying this official update is the recommended remediation.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-05-08T20:44:38.964Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a052a70cbff5d86103e0d89
Added to database: 05/14/2026, 01:50:40 UTC
Last enriched: 05/21/2026, 12:25:07 UTC
Last updated: 07/31/2026, 19:22:59 UTC
Views: 165
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