CVE-2026-43417

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

Description An issue exists in the sched/mmcid component regarding the handling of vfork() and CLONE VM. A logic error occurs when the number of tasks associated with a process is smaller than the number of MMCID users. The system incorrectly accounts for already processed tasks while searching the task list for a vfork()ed task. If this leads to the number of tasks to be handled reaching zero, the walk stops without fixing the vfork()ed task's CID. This results in a failure to acquire a transitional CID during a subsequent schedule in, causing the machine to stall. This can lead to a state where a task endlessly loops in the mm get cid() function.

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