dbcve.org
CWE-15Weakness · CWE-15

CVE-2026-41489

HIGH · 8.8 CVSS v3.1 Published 2026-05-11
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
90/100
Remediation priority · Urgent
Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
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.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

Pi-hole versions 6.0 through Core before 6.4.2 and FTL before 6.6.1 contain a local privilege escalation vulnerability. Two systemd service scripts (pihole-FTL-prestart.sh and pihole-FTL-poststop.sh) execute as root and read the files.pid path from configuration without validation. An attacker with pihole user privileges can write an arbitrary path to the config, causing root to delete and recreate any file outside ProtectSystem=restricted directories via install and rm -f commands. This enables root escalation via SSH authorized_keys manipulation.

MitigationUpgrade Pi-hole Core to 6.4.2 or later and FTL to 6.6.1 or later. If immediate patching is not possible, restrict pihole user access and monitor for unauthorized modifications to the files.pid configuration option.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Scope
Changed
Confidentiality
High
Integrity
High
Availability
High

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

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify Pi-hole Core and FTL versions
    Run `pihole -v` to display installed Pi-hole Core and FTL version numbers
    Affected if Installed versions are below Core 6.4.2 or FTL 6.6.1
  2. Locate the systemd service scripts
    Find pihole-FTL-prestart.sh and pihole-FTL-poststop.sh using `find / -name 'pihole-FTL-prestart.sh' -o -name 'pihole-FTL-poststop.sh' 2>/dev/null`
    Affected if These scripts exist and are executable by the pihole user or group
  3. Inspect the FTL config for files.pid setting
    Locate the pihole FTL config file (commonly /etc/pihole/pihole-FTL.conf) and check for a files.pid= entry
    Affected if A files.pid setting exists and points to a path outside /run or /var/run (the default protected directories)
  4. Check config file ownership and permissions
    Run `ls -la` on the pihole-FTL.conf file to verify it is writable by the pihole user or group
    Affected if The pihole user or a group the attacker belongs to has write access to the config file
  5. Audit SSH authorized_keys for unauthorized entries
    Inspect /root/.ssh/authorized_keys for any unexpected public keys
    Affected if Any unfamiliar public keys are present in /root/.ssh/authorized_keys

A user is affected if they run Pi-hole Core below 6.4.2 or FTL below 6.6.1, the pihole user has write access to the config file, and the files.pid path can be manipulated to target files outside protected directories.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Upgrade Pi-hole Core to 6.4.2 or later and FTL to 6.6.1 or later. If immediate patching is not possible, restrict pihole user access and monitor for unauthorized modifications to the files.pid configuration option.

Recommended fix High confidence

Pi-hole Core 6.4.2 and FTL 6.6.1

  1. Check current Pi-hole Core and FTL versions using: pihole -v
  2. Upgrade Pi-hole Core to version 6.4.2 or later using: pihole -up
  3. Upgrade Pi-hole FTL to version 6.6.1 or later using: pihole -up
  4. Verify the upgrade was successful by checking: pihole -v
  5. Ensure the pihole-FTL-prestart.sh and pihole-FTL-poststop.sh scripts now properly validate the files.pid path
Caveat Review Pi-hole 6.x release notes for any configuration or migration requirements before upgrading

Generated from the published advisory — verify against the referenced sources before acting.

Have this fixed Scoped from the published advisory
  • Consultation2.0 h
  • Implementation2.0 h
  • Testing2.0 h
  • Review / QA1.0 h
7.0 hours of engineering $1,240
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,984.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2026-41489 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-41489 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data