CVE-2026-35491: Pi-hole FTL: CLI API sessions can import Teleporter archives and modify configuration

Severity: medium (CVSS 6.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2026-04-07 · updated 2026-10-26
Weakness: CWE-863

Description

FTLDNS (pihole-FTL) provides an interactive API and also generates statistics for Pi-hole's Web interface. From 6.0 to before 6.6, Pi-hole FTL supports a CLI password feature (webserver.api.cli_pw) that creates “CLI” API sessions intended to be read-only for configuration changes. While /api/config correctly blocks CLI sessions from mutating configuration, /api/teleporter allowed Teleporter imports for CLI sessions, enabling a CLI-scoped session to overwrite configuration via a Teleporter archive (authorization bypass). This vulnerability is fixed in 6.6.

Affected products

pi-hole FTL: from 6.0 before 6.6 — fixed in 6.6

How to fix

Upgrade to a fixed version: pi-hole FTL 6.6. Check the vendor advisory for mitigations.

References

https://github.com/pi-hole/FTL/security/advisories/GHSA-r7g8-3fj7-m5qq

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