CVE-2025-21687: linux kernel Out-of-bounds Read — Fix

Description

In the Linux kernel, the following vulnerability has been resolved: vfio/platform: check the bounds of read/write syscalls count and offset are passed from user space and not checked, only offset is capped to 40 bits, which can be used to read/write out of bounds of the device.

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CVSS v3.1 Score

7.8

HIGH

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Weakness Type (CWE)

CWE-125 Out-of-bounds Read

CWE-787 Out-of-bounds Write

Affected Products

Vendor	Product	Versions
linux	linux_kernel	4.1 — 5.4.290
linux	linux_kernel	5.5 — 5.10.234
linux	linux_kernel	5.11 — 5.15.178
linux	linux_kernel	5.16 — 6.1.128
linux	linux_kernel	6.2 — 6.6.75
linux	linux_kernel	6.7 — 6.12.12
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All

References

Advisories & Patches

Other References

https://git.kernel.org/stable/c/9377cdc118cf327248f1a9dde7b87de067681dc9 https://git.kernel.org/stable/c/ed81d82bb6e9df3a137f2c343ed689e6c68268ef https://git.kernel.org/stable/c/f65ce06387f8c1fb54bd59e18a8428248ec68eaf https://lists.debian.org/debian-lts-announce/2025/03/msg00001.html https://lists.debian.org/debian-lts-announce/2025/03/msg00002.html

Frequently Asked Questions

What is CVE-2025-21687? +

In the Linux kernel, the following vulnerability has been resolved: vfio/platform: check the bounds of read/write syscalls count and offset are passed from user space and not checked, only offset is capped to 40 bits, which can be used to read/write out of bounds of the device. It has a CVSS v3.1 base score of 7.8 (HIGH).

How severe is CVE-2025-21687? +

CVE-2025-21687 has a CVSS v3.1 score of 7.8 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.

What products are affected by CVE-2025-21687? +

CVE-2025-21687 affects products from linux, specifically: linux_kernel. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-21687? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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