CVE-2026-41489: pi-hole

Vulnerability summary

CVE-2026-41489 is a high (CVSS 8.8) vulnerability in pi-hole. EPSS estimates a 0.19% chance of exploitation in the next 30 days, higher than 8.1% of scored vulnerabilities.

Timeline

1. 11-05-2026
   PublishedVulnerability first disclosed.
2. 13-05-2026
   Last modifiedVulnerability information updated.

Description

Pi-hole is a DNS sinkhole that protects devices from unwanted content without installing any client-side software. From 6.0 to before Core 6.4.2 and FTL 6.6.1, two shell scripts executed as root by systemd (pihole-FTL-prestart.sh and pihole-FTL-poststop.sh) read the files.pid path from this config without validation and use it in privileged file operations (install and rm -f). By writing an arbitrary path into files.pid, an attacker with pihole privilege can cause root to delete and then recreate any file on the system outside the ProtectSystem=full-restricted directories, gaining write access to it. On a default Pi-hole installation this yields local privilege escalation to root via SSH authorized keys manipulation. If /root/.ssh/authorized_keys does not exist (default on fresh installs), only ExecStartPre is required. If the file exists, ExecStopPost deletes it first, and the same restart triggers both hooks in sequence. This vulnerability is fixed in Core 6.4.2 and FTL 6.6.1.

• CWE-15External Control of System or Configuration SettingOne or more system settings or configuration elements can be externally controlled by a user.
• CWE-269Improper Privilege ManagementThe product does not properly assign, modify, track, or check privileges for an actor, creating an unintended sphere of control for that actor.
• CWE-732Incorrect Permission Assignment for Critical ResourceThe product specifies permissions for a security-critical resource in a way that allows that resource to be read or modified by unintended actors.