Pi-hole: Local privilege escalation from `pihole` user to root via CVE-2026-41489 fix bypass

Pi-hole is a DNS sinkhole that protects devices from unwanted content without installing any client-side software. Prior to 6.5, advanced/Scripts/utils.sh getFTLPID() attempts to validate the pihole-owned /run/pihole-FTL.pid file with expr "${FTL_PID}" : "[^[:digit:]]", but this rejects only values whose first character is not a digit. An attacker with code execution as the pihole user can write a digit-prefixed arithmetic expression to the pihole-owned PID file. Root-run pihole subcommands then evaluate [[ "$pid" -eq "-1" ]], causing Bash to recursively evaluate array subscripts and execute command substitution as root. This bypasses the content-validation portion of the CVE-2026-41489 remediation while leaving its hardcoded PID-file path protection intact. This issue is fixed in version 6.5.

Pi-hole: arbitrary root file clobber / chmod / disclosure via updatecheck.sh cron following /etc/pihole/versions symlink

Pi-hole is a DNS sinkhole that protects devices from unwanted content without installing any client-side software. From 6.4.2 until 6.5, the root-run advanced/Scripts/updatecheck.sh cron job applies truncate -s 0 and chmod 644 to /etc/pihole/versions while following symbolic links in a directory owned by the pihole user. An attacker executing as pihole can replace that path with a symlink so the scheduled root operations truncate or create an arbitrary root-owned file, or race the operations so chmod makes a sensitive target world-readable without truncating it. This issue is fixed in version 6.5.

Pi-hole: file:// adlist read check and curl can resolve different files

Pi-hole is a DNS sinkhole that protects devices from unwanted content without installing any client-side software. Prior to 6.5, gravity.sh checks file:// adlist readability with sudo -u pihole test -r but then allows curl, sometimes running as root, to normalize URL dot segments and open a different file. A pihole-readable decoy can therefore pass the check while curl reads a root-only target, and /proc/self paths can similarly resolve against different processes. Exploitation requires an administrator who can add adlists and can place a symlink and decoy on the filesystem. This issue is fixed in version 6.5.

Pi-hole: Local privilege escalation from `pihole` user to root via `/etc/pihole/logrotate`

Pi-hole is a DNS sinkhole that protects devices from unwanted content without installing any client-side software. From 6.0 to 6.4.2, a user with code execution as the unprivileged pihole user can escalate to root by replacing /etc/pihole/logrotate. The replacement is laundered to root:root ownership by pihole-FTL-prestart.sh and then parsed as root by the daily pihole flush cron, executing firstaction shell as uid 0. This issue is fixed in version 6.4.3.

Pi-hole: Local privilege escalation via config-controlled path in root-executed service hooks

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.

Pi-hole has a Local Privilege Escalation (post-compromise, pihole -> root).

Pi-hole is a Linux network-level advertisement and Internet tracker blocking application. Version 6.4 has a local privilege-escalation vulnerability allows code execution as root from the low-privilege pihole account. Important context: the pihole account uses nologin, so this is not a direct interactive-login issue. However, nologin does not prevent code from running as UID pihole if a Pi-hole component is compromised. In that realistic post-compromise scenario, attacker-controlled content in /etc/pihole/versions is sourced by root-run Pi-hole scripts, leading to root code execution. This vulnerability is fixed in 6.4.1.

Multiple Privilege Escalation Vulnerabilities Pihole

Pi-hole is a Linux network-level advertisement and Internet tracker blocking application. Multiple privilege escalation vulnerabilities were discovered in version 5.2.4 of Pi-hole core. See the referenced GitHub security advisory for details.

Pi-hole Admin Interface vulnerable to cross-site scripting via malformed URL path on 404 error page

Pi-hole Admin Interface is a web interface for managing Pi-hole, a network-level advertisement and internet tracker blocking application. Pi-hole Admin Interface versions 6.2.1 and earlier are vulnerable to reflected cross-site scripting (XSS) via a malformed URL path. The 404 error page includes the requested path in the class attribute of the body tag without proper sanitization or escaping. An attacker can craft a URL containing an onload attribute that will execute arbitrary JavaScript code in the browser when a victim visits the malicious link. If an attacker sends a crafted pi-hole link to a victim and the victim visits it, attacker-controlled JavaScript code is executed in the browser of the victim. This has been patched in version 6.3.

Pi-hole Admin Interface vulnerable to HTTP response header injection via CRLF injection

Pi-hole Admin Interface is a web interface for managing Pi-hole, a network-level advertisement and internet tracker blocking application. Pi-hole Admin Interface before 6.3 is vulnerable to Carriage Return Line Feed (CRLF) injection. When a request is made to a file ending with the .lp extension, the application performs a redirect without properly sanitizing the input. An attacker can inject carriage return and line feed characters (%0d%0a) to manipulate both the headers and the content of the HTTP response. This enables the injection of arbitrary HTTP response headers, potentially leading to session fixation, cache poisoning, and the weakening or bypassing of browser-based security mechanisms such as Content Security Policy or X-XSS-Protection. This vulnerability is fixed in 6.3.

Pi-hole Admin Interface vulnerable to persistent XSS on Subscribed lists group management (Adress Field)

Pi-hole Admin Interface is a web interface for managing Pi-hole, a network-level advertisement and internet tracker blocking application. Pi-hole Admin Interface versions prior to 6.3 are vulnerable to cross-site scripting (XSS) via the Address field in the Subscribed Lists group management section. An authenticated user can inject malicious JavaScript by adding a payload to the Address field when creating or editing a list entry. The vulnerability is triggered when another user navigates to the Tools section and performs a gravity database update. The Address field does not properly sanitize input, allowing special characters and script tags to bypass validation. This has been patched in version 6.3.

Pi-Hole AdminLTE Whitelist (now 'Web Allowlist') Remote Command Execution

An authenticated command injection vulnerability exists in Pi-hole versions up to 3.3. When adding a domain to the allowlist via the web interface, the domain parameter is not properly sanitized, allowing an attacker to append OS commands to the domain string. These commands are executed on the underlying operating system with the privileges of the Pi-hole service user. This behavior was present in the legacy AdminLTE interface and has since been patched in later versions.

Pi-hole Web v4.3.2 (aka AdminLTE) allows Remote Code Execution by privileged dashboard users via a crafted DHCP static lease.

Pihole Authenticated Arbitrary File Read with root privileges

The Pi-hole is a DNS sinkhole that protects your devices from unwanted content without installing any client-side software. A vulnerability has been discovered in Pihole that allows an authenticated user on the platform to read internal server files arbitrarily, and because the application runs from behind, reading files is done as a privileged user.If the URL that is in the list of "Adslists" begins with "file*" it is understood that it is updating from a local file, on the other hand if it does not begin with "file*" depending on the state of the response it does one thing or another. The problem resides in the update through local files. When updating from a file which contains non-domain lines, 5 of the non-domain lines are printed on the screen, so if you provide it with any file on the server which contains non-domain lines it will print them on the screen. This vulnerability is fixed by 5.18.

Pi-hole before 6 allows unauthenticated admin/api.php?setTempUnit= calls to change the temperature units of the web dashboard. NOTE: the supplier reportedly does "not consider the bug a security issue" but the specific motivation for letting arbitrary persons change the value (Celsius, Fahrenheit, or Kelvin), seen by the device owner, is unclear.

Pi-hole Blind Server-Side Request Forgery (SSRF) vulnerability can lead to Remote Code Execution (RCE)

Pi-hole is a DNS sinkhole that protects devices from unwanted content without installing any client-side software. A vulnerability in versions prior to 5.18.3 allows an authenticated user to make internal requests to the server via the `gravity_DownloadBlocklistFromUrl()` function. Depending on some circumstances, the vulnerability could lead to remote command execution. Version 5.18.3 contains a patch for this issue.

Stored XSS Vulnerability in the Pi-hole Webinterface

Pi-hole's Web interface provides a central location to manage a Pi-hole instance and review performance statistics. Prior to Pi-hole Web interface version 5.5.1, the function to add domains to blocklists or allowlists is vulnerable to a stored cross-site-scripting vulnerability. User input added as a wildcard domain to a blocklist or allowlist is unfiltered in the web interface. Since the payload is stored permanently as a wildcard domain, this is a persistent XSS vulnerability. A remote attacker can therefore attack administrative user accounts through client-side attacks. Pi-hole Web Interface version 5.5.1 contains a patch for this vulnerability.

(Authenticated) Remote Code Execution Possible in Web Interface 5.5

Pi-hole's Web interface provides a central location to manage a Pi-hole instance and review performance statistics. Prior to Pi-hole Web interface version 5.5.1, the `validDomainWildcard` preg_match filter allows a malicious character through that can be used to execute code, list directories, and overwrite sensitive files. The issue lies in the fact that one of the periods is not escaped, allowing any character to be used in its place. A patch for this vulnerability was released in version 5.5.1.

Stored DOM XSS in Pi-hole Admin Web Interface

Pi-hole is a Linux network-level advertisement and Internet tracker blocking application. The Stored XSS exists in the Pi-hole Admin portal, which can be exploited by the malicious actor with the network access to DNS server. See the referenced GitHub security advisory for patch details.

The DNS query log in Pi-hole before 5.2.2 is vulnerable to stored XSS. An attacker with the ability to directly or indirectly query DNS with a malicious hostname can cause arbitrary JavaScript to execute when the Pi-hole administrator visits the Query Log or Long-term data Query Log page.

Pi-hole 5.0, 5.1, and 5.1.1 allows XSS via the Options header to the admin/ URI. A remote user is able to inject arbitrary web script or HTML due to incorrect sanitization of user-supplied data and achieve a Reflected Cross-Site Scripting attack against other users and steal the session cookie.