CVE-2025-38733

Severity CVSS v4.0:

Pending analysis

Type:

CWE-476 NULL Pointer Dereference

Publication date:

05/09/2025

Last modified:

25/11/2025

Description

In the Linux kernel, the following vulnerability has been resolved: s390/mm: Do not map lowcore with identity mapping Since the identity mapping is pinned to address zero the lowcore is always also mapped to address zero, this happens regardless of the relocate_lowcore command line option. If the option is specified the lowcore is mapped twice, instead of only once. This means that NULL pointer accesses will succeed instead of causing an exception (low address protection still applies, but covers only parts). To fix this never map the first two pages of physical memory with the identity mapping.

Impact

Vector 3.x

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H CVSS v3.1 Severity and Metrics:

Base Score: 5.50 MEDIUM
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Attack Vector (AV): Local
Attack Complexity (AC): Low
Privileges Required (PR): Low
User Interaction (UI): None
Scope (S): Unchanged
Confidentiality (C): None
Integrity (I): None
Availability (A): High

Base Score 3.x

5.50

Severity 3.x

MEDIUM

Vulnerable products and versions

CPE	From	Up to
cpe:2.3:o:linux:linux_kernel::::::::	6.10.11 (including)	6.11 (excluding)
cpe:2.3:o:linux:linux_kernel::::::::	6.11.1 (including)	6.12.44 (excluding)
cpe:2.3:o:linux:linux_kernel::::::::	6.13 (including)	6.16.4 (excluding)
cpe:2.3:o:linux:linux_kernel:6.11:-::::::
cpe:2.3:o:linux:linux_kernel:6.11:rc5::::::
cpe:2.3:o:linux:linux_kernel:6.11:rc6::::::
cpe:2.3:o:linux:linux_kernel:6.11:rc7::::::
cpe:2.3:o:linux:linux_kernel:6.17:rc1::::::
cpe:2.3:o:linux:linux_kernel:6.17:rc2::::::

To consult the complete list of CPE names with products and versions, see this page

CVE-2025-38733

Description

Impact

Vulnerable products and versions

References to Advisories, Solutions, and Tools