CVE-2026-111231: Netgate pfSense CE through 2.9.0 Authorization Bypass via config_restore() and config_install()

Severity: high (CVSS 7.2 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.8% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-10-15 · updated 2026-10-26
Weakness: CWE-863

Description

Netgate pfSense CE through 2.9.0 contains an authorization bypass vulnerability that allows read-only WebGUI users to replace config.xml because config_restore() and config_install() ignore the 'User - Config: Deny Config Write' privilege. Attackers holding page privileges for services_acb.php, uploadconfig.php, diag_confbak.php, or diag_backup.php can install a chosen config.xml to gain root-level code execution after reload or reboot.

Affected products

Netgate pfSense CE: through 2.9.0

References

https://abraxaslabs.tech/research/pfsense-ce-leftovers
https://github.com/abraxas/pfsense-config-readonly-restore
https://github.com/pfsense/pfsense/blob/9363ac5b8651a1c7a333180425ce7719070f95f9/src/etc/inc/config.lib.inc#L588-L597
https://github.com/pfsense/pfsense/blob/9363ac5b8651a1c7a333180425ce7719070f95f9/src/etc/inc/config.lib.inc#L743-L798
https://www.vulncheck.com/advisories/netgate-pfsense-ce-through-2.9.0-authorization-bypass-via-config-restore-and-config-install

Get alerted when CVE-2026-111231 or the next vulnerability affects your stack