CVE-2026-111229: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection') in Netgate pfSense CE
Description
pfSense CE versions 2.7.0 through 2.9.0 contain a command injection vulnerability in the captive portal HA synchronization feature. This flaw allows users with the Captive Portal HA privilege to execute arbitrary commands as root by exploiting unescaped shell metacharacters in data returned from a malicious XMLRPC server.
CVSS v4.0
Score 8.6high
Affected software
Netgate
pfSense CE
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-111229 is an OS command injection vulnerability in Netgate pfSense CE affecting versions 2.7.0 through 2.9.0. The issue exists in services_captiveportal_hasync.php where the captive portal HA synchronization feature processes data from a backwardsyncip XMLRPC server. If an attacker controls this server, they can return connected_users data containing shell metacharacters in the ip or mac fields. These fields are passed unescaped to a pfctl shell command, enabling command injection and execution with root privileges by users holding the Captive Portal HA privilege.
Potential Impact
An attacker with the Captive Portal HA privilege can execute arbitrary commands as root on the pfSense CE system. This can lead to full system compromise, unauthorized access, and control over the firewall device.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, restrict access to users with the Captive Portal HA privilege and avoid configuring backwardsyncip to untrusted XMLRPC servers.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- VulnCheck
- Date Reserved
- 2026-10-15T18:21:23.312Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6ad123be2cdf04f65652b74e
Added to database: 10/15/2026, 19:04:30 UTC
Last enriched: 10/15/2026, 19:18:26 UTC
Last updated: 10/15/2026, 19:19:21 UTC
Views: 9
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