Bug 2376035 (CVE-2025-38110)

Summary: CVE-2025-38110 kernel: net/mdiobus: Fix potential out-of-bounds clause 45 read/write access
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
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OS: Linux   
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Description OSIDB Bzimport 2025-07-03 09:01:27 UTC
In the Linux kernel, the following vulnerability has been resolved:

net/mdiobus: Fix potential out-of-bounds clause 45 read/write access

When using publicly available tools like 'mdio-tools' to read/write data
from/to network interface and its PHY via C45 (clause 45) mdiobus,
there is no verification of parameters passed to the ioctl and
it accepts any mdio address.
Currently there is support for 32 addresses in kernel via PHY_MAX_ADDR define,
but it is possible to pass higher value than that via ioctl.
While read/write operation should generally fail in this case,
mdiobus provides stats array, where wrong address may allow out-of-bounds
read/write.

Fix that by adding address verification before C45 read/write operation.
While this excludes this access from any statistics, it improves security of
read/write operation.

Comment 1 Avinash Hanwate 2025-07-03 20:23:38 UTC
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2025070324-CVE-2025-38110-a9c0@gregkh/T

Comment 4 errata-xmlrpc 2025-07-15 21:04:25 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.4 Extended Update Support

Via RHSA-2025:11245 https://access.redhat.com/errata/RHSA-2025:11245

Comment 5 errata-xmlrpc 2025-07-28 08:23:51 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 10

Via RHSA-2025:11855 https://access.redhat.com/errata/RHSA-2025:11855

Comment 6 errata-xmlrpc 2025-07-28 10:05:07 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9

Via RHSA-2025:11861 https://access.redhat.com/errata/RHSA-2025:11861