A null pointer dereference occurs in the Linux kernel's crypto subsystem within the ccp/sev-dev-tsm driver. The dsm_create function assumes that pdev->bus is non‑NULL, but when it is NULL the function proceeds to dereference it unconditionally using pcie_find_root_port and pci_dev_id. This leads to a kernel crash, causing a denial of service. The flaw does not directly disclose data or alter system integrity; it mainly disrupts availability by forcing a kernel panic during cryptographic device initialization. Based on the description, it is a classic Null Pointer Dereference weakness (CWE-476).

Any Linux kernel installation that has not applied the bug fix will be vulnerable. The vulnerability is present in all kernel versions where the ccp/sev-dev-tsm driver contains the flawed dsm_create implementation. Because the fix was authored in the kernel source, distributions that have incorporated the patch into their kernel releases are no longer impacted; all other distributions remain affected until they update to a kernel version that contains the change.

The CVSS score is not provided, and the EPSS score is unavailable, so the overall risk assessment relies on the potential impact and the known exploitability. The flaw is a local kernel vulnerability—an attacker would need to execute code that triggers dsm_create, such as running privileged build tools or modules that load the SEV device. There is no published public exploit, and the flaw is not listed in the CISA KEV catalog. Nevertheless, a local attacker could force a denial of service by inducing a kernel panic, thereby impacting system availability. The risk is elevated for environments where kernel modules can be loaded from untrusted sources or where the SEV device is exposed to privileged users without proper isolation.