CVE-2026-98171

A flaw was found in the Linux kernel's Server Message Block (SMB) client. A malicious or compromised remote server can exploit this flaw by sending specially crafted compound encrypted network responses. Due to improper bounds validation and pointer lifecycle management, the client can encounter a use-after-free condition or out-of-bounds memory access. This flaw primarily allows an attacker to cause a system crash, leading to a denial of service (DoS), or potentially execute arbitrary code.

This vulnerability is rated as Important severity for Red Hat Enterprise Linux because an attacker must control or compromise a remote SMB server and entice a client to connect, yet successful exploitation can yield kernel memory corruption. In typical enterprise environments, the SMB client kernel module is not active unless a CIFS filesystem is explicitly mounted by an administrator or user. However, systems that connect to untrusted file shares or follow dynamic server referrals are exposed to malformed encrypted responses that can cause a kernel crash or privilege escalation.

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.