CVE-2026-72183

A flaw was found in the Linux kernel's Landlock security module. A sandboxed process can bypass the intended signal isolation provided by LANDLOCK_SCOPE_SIGNAL. By manipulating file descriptors with specific fcntl calls and asynchronous I/O (SIGIO) delivery, a local attacker can send signals, such as a kill signal, to processes outside its Landlock domain. This could lead to a denial of service or unauthorized process termination of critical system processes.

This vulnerability is rated as Moderate impact because exploitation requires local access and is constrained to environments where applications actively enforce Landlock signal scoping while sharing process groups with unconfined processes. An unprivileged task could leverage asynchronous I/O notifications to dispatch unexpected signals across its containment perimeter, potentially terminating supervisor or peer tasks. The flaw does not grant elevated privileges or compromise data confidentiality. Systems hosting workloads that do not implement Landlock signal restrictions remain unaffected.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.