CVE-2026-53403

Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)

Description A null-pointer dereference occurs in the fb videomode to var() function within the fbdev component. The issue arises when store modes() replaces the modelist from userspace via fb new modelist(). While fb new modelist() validates new modes, it fails to ensure that the current framebuffer mode info->var still has a matching entry in the updated info->modelist. If the framebuffer console (fbcon) is unbound, info->var may describe a mode no longer present in the list. Subsequently, a console takeover triggers var to display(), where fb match mode() returns NULL, leading fbcon switch() to pass a NULL mode to display to var(), which is then dereferenced by fb videomode to var().

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.