Description
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.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
pi-hole pi-hole
< 6.5affected