CVE-2026-44194CWE-78

OPNsense: RCE on user managment

Critical · published May 13, 2026

CVSS v3.1
9.1
EPSS
1%
Percentile
56.9
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
9.1 · CRITICAL
Vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
CVSS v4.0
Not supplied
EPSS
0.00820 · 56.9th percentile
Weakness
CWE-78 · Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
Published
2026-05-13T21:53Z
EPSS history
Timeline
  • 13 MAY 21:53Z
    OPNsense: RCE on user managment
    cvelistv5