CVE-2026-72422

A flaw was found in ksmbd, the in-kernel SMB3 server for Linux. A remote attacker could exploit a use-after-free vulnerability by sending specially crafted concurrent SMB2 NEGOTIATE requests on the same connection. This could lead to memory corruption, potentially allowing the attacker to execute arbitrary code or cause a denial of service on the system.

This vulnerability is rated as Moderate impact because the in-kernel SMB server module (ksmbd) is neither loaded nor active by default in Red Hat Enterprise Linux, significantly restricting exposure to non-standard environments. Exploiting this race condition requires the ksmbd service to be explicitly configured and processing network traffic, where parallel negotiation requests on an established connection can trigger slab memory corruption. Deployments relying on the default Samba user-space daemon (smbd) are unaffected by this flaw.

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.