Critical cPanel Flaw Could Let One Hosting Customer Take Root Control of a Whole Server
cPanel patched critical flaw CVE-2026-65643 letting authenticated hosting customers with addon or parked domain rights execute code as root and fully compromise servers.
cPanel issued patches on August 27, 2026 for CVE-2026-65643, a flaw in domain parking and addon domain functionality in cPanel & WHM that lets an authenticated account holder create arbitrary files and execute code as root, yielding full server control. Fixed builds cover the 11.110, 11.134, 11.136 and 11.138 branches, including WP Squared 11.138.1.7, and auto-update servers receive the fix automatically. No CVSS score, published CVE record, or evidence of exploitation has appeared, and the flaw is absent from CISA's KEV catalog as of August 27. The article also recaps related 2026 cPanel-ecosystem issues, including KEV-listed LiteSpeed plugin flaws and the in-the-wild-exploited Phusion Passenger problem.