CVE-2026-49954: Improper Control of Filename for Include/Require Statement in PHP Program

Discuz! X5.0 releases 20260320 through 20260610 contain a local file inclusion vulnerability that allows authenticated administrators to execute arbitrary code by importing a specially crafted plugin configuration containing path traversal sequences in the directory attribute. Attackers can trigger an exception during plugin installation to bypass sanitization routines, causing malicious paths to be stored unsanitized and subsequently passed to include(), which combined with file upload functionality escalates to arbitrary code execution in the context of the web server user.