CVE-2026-44194 (GCVE-0-2026-44194)
Vulnerability from cvelistv5 – Published: 2026-05-13 21:53 – Updated: 2026-05-19 03:55
VLAI
EPSS
VEX
Title
OPNsense: RCE on user managment
Summary
OPNsense is a FreeBSD based firewall and routing platform. Prior to 26.1.8, an authenticated Remote Code Execution (RCE) vulnerability in the OPNsense core allows a user with user-management privileges to execute arbitrary system commands as root. An attacker can bypass input validation by formatting their malicious payload as a compliant email address, allowing shell commands to reach the underlying operating system. The flaw exists in the local user synchronization flow, within core/src/opnsense/scripts/auth/sync_user.php. This vulnerability is fixed in 26.1.8.
Severity
9.1 (Critical)
SSVC
Exploitation: poc
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-15 00:00 UTC
CWE
- CWE-78 - Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
Assigner
References
1 reference
| URL | Tags |
|---|---|
| https://github.com/opnsense/core/security/advisor… | x_refsource_CONFIRM |
Impacted products
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Browse all ATT&CK techniques and the vulnerabilities related to each.
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