AZL-104673

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Import Source
https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-104673.json
JSON Data
https://api.osv.dev/v1/vulns/AZL-104673
Upstream
Published
2026-09-25T11:17:29Z
Modified
2026-09-27T05:34:32Z
Summary
CVE-2026-98008 affecting package kernel 6.6.157.1-1
Details

In the Linux kernel, the following vulnerability has been resolved:

net: macb: fix NULL pointer dereference on unbind with fixed-link

When the device tree describes a fixed-link and has no "mdio" child node, macb_mii_init() returns early without allocating the MDIO bus, leaving bp->mii_bus as NULL.

Two cleanup paths then dereference this NULL bus:

  1. On driver unbind, macb_remove() unconditionally calls mdiobus_unregister(bp->mii_bus), which oopses:

Unable to handle kernel NULL pointer dereference at virtual address 00000000000004a8 pc : mdiobus_unregister+0x14/0xa4 lr : macb_remove+0x38/0xa4 Call trace: mdiobus_unregister+0x14/0xa4 (P) macb_remove+0x38/0xa4 platform_remove+0x20/0x30 device_release_driver_internal+0x1c8/0x224 unbind_store+0xb4/0xbc

  1. On the probe error path in macb_probe(), reached when macb_mii_init() has succeeded but a subsequent step fails, the err_out_unregister_mdio label runs the same unconditional cleanup.

mdiobus_unregister() and mdiobus_free() do not guard against a NULL bus, so guard the calls in both macb_remove() and the probe error path.

References

Affected packages

Azure Linux:3 / kernel

Package

Name
kernel
Purl
pkg:rpm/azure-linux/kernel

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected
Last Affected
6.6.157.1-1

Database specific

source
"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-104673.json"