CVE-2026-44194

OPNsense: RCE on user managment

State: Published
Severity: 9.1 Critical
Published: May 13, 2026
Updated: May 19, 2026
Reserved: May 5, 2026

Description

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.

Scores

CVSS	Score	Vector	Source
3.1	9.1 Critical	CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H	GitHub_M

Weaknesses

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

Affected Products

Product	Versions
coreopnsense	< 26.1.8Affected

References

https://github.com/opnsense/core/security/advisories/GHSA-f59w-m967-9rf6

Every record here comes from the CVE Program’s CVE List. © 1999–2026 The MITRE Corporation. CVE is a registered trademark of The MITRE Corporation. The records are reproduced under the CVE Program terms of use.