CVE-2026-52980

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

Description A crash can occur when a newly forked sched entity enters the fair class with se->rel deadline unexpectedly set. This happens because the sched fork() function fails to clear rel deadline during initialization. Consequently, the place entity() function, called by enqueue entity(), treats se->deadline as a relative deadline and converts it into an abnormally large absolute deadline by adding the current vruntime.

If the task subsequently calls sched yield(), the yield task fair() function advances se->vruntime to this inflated deadline. This value can cause an overflow when multiplied by the entity weight during the enqueue path, corrupting cfs rq->sum w vruntime and breaking EEVDF (Earliest Eligible Virtual Deadline First) eligibility calculations. This may result in all entities appearing ineligible, causing pick next entity() to return NULL and leading to a NULL dereference crash.

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