CVE-2025-38733

5.5 MEDIUM
Published: September 05, 2025 Modified: November 25, 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.

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CVSS v3.x Details

0.0 Low Medium High Critical 10.0
Vector String
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
https://git.kernel.org/stable/c/1d7864acd497cb468a998d44631f84896f885e85
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Patch
https://git.kernel.org/stable/c/30bf5728bb217a6d1ba73f44094c9b9c6bc9a567
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Patch
https://git.kernel.org/stable/c/93f616ff870a1fb7e84d472cad0af651b18f9f87
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Patch

3 reference(s) from NVD

Quick Stats

CVSS v3 Score
5.5 / 10.0
EPSS (Exploit Probability)
0.0%
4th percentile
Exploitation Status
Not in CISA KEV

Weaknesses (CWE)

Affected Vendors

linux