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.

Pi-hole 5.0, 5.1, and 5.1.1 allows Session Fixation. The application does not generate a new session cookie after the user is logged in. A malicious user is able to create a new session cookie value and inject it to a victim. After the victim logs in, the injected cookie becomes valid, giving the attacker access to the user's account through the active session.

Pi-hole through 5.0 allows code injection in piholedhcp (the Static DHCP Leases section) by modifying Teleporter backup files and then restoring them. This occurs in settings.php. To exploit this, an attacker would request a backup of limited files via teleporter.php. These are placed into a .tar.gz archive. The attacker then modifies the host parameter in dnsmasq.d files, and then compresses and uploads these files again.

An issue was discovered in Pi-Hole through 5.0. The local www-data user has sudo privileges to execute the pihole core script as root without a password, which could allow an attacker to obtain root access via shell metacharacters to this script's setdns command.

Pi-hole 4.4 allows a user able to write to /etc/pihole/dns-servers.conf to escalate privileges through command injection (shell metacharacters after an IP address).

The Gravity updater in Pi-hole through 4.4 allows an authenticated adversary to upload arbitrary files. This can be abused for Remote Code Execution by writing to a PHP file in the web directory. (Also, it can be used in conjunction with the sudo rule for the www-data user to escalate privileges to root.) The code error is in gravity_DownloadBlocklistFromUrl in gravity.sh.

Pi-Hole 4.3 allows Command Injection.