CVE-2026-111231

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.

CVSS 4.0

8.6CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

CVSS 3.1

7.2CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

EPSS

0.8% chance of exploitation in the next 30 days; higher than 57% of CVEs (scores of 2026-10-25)

CWE

CWE-863

Published

2026-10-15

Modified

2026-10-19

Record from

the NVD, synced 2026-10-21

Affected

• pfsense:pfsense

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

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