What is CVE-2026-44194?

CVE-2026-44194 is a critical-severity vulnerability in Opnsense Core, classified under OS Command Injection. CVSS score: 9.1/10. Published 2026-05-13.

How severe is CVE-2026-44194?

Critical severity. CVSS v3 base score is 9.1 out of 10.

RCE in Opnsense Core

CVE-2026-44194

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.

Vulnerability class: Command Injection (OS Command Injection)

EPSS: 0.064 (93.2th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H.

Affected products

Opnsense Core — versions < 26.1.8
Opnsense

Weakness classification (CWE)

CWE-78 — OS Command Injection

References

security-advisories@github.com (x_refsource_CONFIRM, Exploit, Mitigation, Vendor Advisory)

Frequently asked questions

What is CVE-2026-44194?: CVE-2026-44194 is a critical-severity vulnerability in Opnsense Core, classified under OS Command Injection. CVSS score: 9.1/10. Published 2026-05-13.
How severe is CVE-2026-44194?: Critical severity. CVSS v3 base score is 9.1 out of 10.