CVE-2024-50152

A doubly freeing memory vulnerability exists in the Linux kernel smb client. After the first successful memory allocation for 'ea', the second memory release for 'ea' will result in double free, leading to loss of availability of the system.

A moderate impact double-free vulnerability was found in the Linux kernel SMB client, in the smb2_set_ea() function in fs/smb/client/smb2ops.c. If an SMB2 set-extended-attributes operation fails after a successful memory allocation for the EA buffer and the request is subsequently retried through the replay path, the already freed EA pointer can be released a second time. This double free can corrupt kernel memory and crash the system, resulting in a denial of service. Red Hat rates this flaw Moderate severity (CVSS 3.1: 5.5, AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H) because triggering it requires local access and privileges and it impacts system availability only; this differs significantly from the 9.8 score in the upstream CVE record, which assumes an unauthenticated network attacker with confidentiality, integrity, and availability impact that the actual code path does not support. Within Red Hat's product scope, this issue affects Red Hat Enterprise Linux 9 (kernel and kernel-rt in the rhel-9.5.z and rhel-9.6 streams), where a fix is being pursued through the kernel team; in the rhel-9.5.z stream the fix was declined, with the fix delivered through the rhel-9.6 stream. Red Hat Enterprise Linux 6, 7, and 8, as well as the hosted OpenShift (ARO/OSD) environments, are not affected. Fedora is affected as a community project and is addressed through the upstream kernel community process.

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.

Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.