CVE-2025-38427

Published Jul 25, 2025

Last updated a year ago

CVSS medium 5.5

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: video: screen_info: Relocate framebuffers behind PCI bridges Apply PCI host-bridge window offsets to screen_info framebuffers. Fixes invalid access to I/O memory. Resources behind a PCI host bridge can be relocated by a certain offset in the kernel's CPU address range used for I/O. The framebuffer memory range stored in screen_info refers to the CPU addresses as seen during boot (where the offset is 0). During boot up, firmware may assign a different memory offset to the PCI host bridge and thereby relocating the framebuffer address of the PCI graphics device as seen by the kernel. The information in screen_info must be updated as well. The helper pcibios_bus_to_resource() performs the relocation of the screen_info's framebuffer resource (given in PCI bus addresses). The result matches the I/O-memory resource of the PCI graphics device (given in CPU addresses). As before, we store away the information necessary to later update the information in screen_info itself. Commit 78aa89d1dfba ("firmware/sysfb: Update screen_info for relocated EFI framebuffers") added the code for updating screen_info. It is based on similar functionality that pre-existed in efifb. Efifb uses a pointer to the PCI resource, while the newer code does a memcpy of the region. Hence efifb sees any updates to the PCI resource and avoids the issue. v3: - Only use struct pci_bus_region for PCI bus addresses (Bjorn) - Clarify address semantics in commit messages and comments (Bjorn) v2: - Fixed tags (Takashi, Ivan) - Updated information on efifb
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Analyzed
Products
linux_kernel

Risk scores

CVSS 3.1

Type
Primary
Base score
5.5
Impact score
3.6
Exploitability score
1.8
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Severity
MEDIUM

Weaknesses

nvd@nist.gov
CWE-401

Social media

Hype score
Not currently trending

  1. CVE-2025-38427 In the Linux kernel, the following vulnerability has been resolved: video: screen_info: Relocate framebuffers behind PCI bridges Apply PCI host-bridge window offset… https://t.co/8EsSn6bMdz

    @CVEnew

    25 Jul 2025

    147 Impressions

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Configurations

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References

Sources include official advisories and independent security research.