CVE-2025-38272

What it actually does

The flaw causes the DSA b53 driver to attempt EEE register access on BCM63xx switches that lack EEE hardware support, resulting in a system hang when external EEE-capable PHYs are present on RGMII ports.

Why it matters to the business

Systems using affected Linux kernel versions on BCM63xx-based networking hardware may experience unexpected freezes or crashes during interface configuration, leading to operational downtime and requiring reboots in embedded or router deployments.

How an attack unfolds

An attacker or automated configuration process connects an EEE-capable PHY to an RGMII port on a BCM63xx switch; when the kernel attempts to enable EEE features, it accesses non-existent registers and hangs the system. Listed threat actors associated with other Linux kernel privilege-escalation issues could chain this for denial-of-service effects.

How to fix it

Upgrade linux-lts packages to fixed versions: Alpaquita stream to 6.6.58-r0, Alpaquita 23 to 6.1.62-r0, or apply the stable GIT commit 3fbe3f4c57fda09f32e13fa05f53a0cc6f500619. Rebuild and reboot systems after update.

How to confirm the fix worked

Confirm the driver contains the switch EEE capability check before EEE configuration; test on BCM63xx hardware with EEE PHYs that the system no longer hangs during interface bring-up.

Typical attack path

1. Identify or deploy hardware with BCM63xx internal switch and EEE-capable external PHY on RGMII port
2. Trigger kernel DSA initialization or ethtool EEE configuration
3. Kernel code path enables EEE without switch capability check
4. Access to non-existent EEE registers causes system hang

How to detect it

Review kernel logs for DSA b53 EEE configuration attempts or unexplained hangs during network initialization on BCM63xx platforms; correlate with ethtool or interface configuration events.

What your security team should do

• Prioritize upgrades on all affected linux-lts deployments within 30 days given 474 days since publication and rising EPSS trend
• Audit network hardware inventories for BCM63xx switches with external PHYs
• Apply kernel updates from distribution channels and verify with package managers
• Monitor for related Linux kernel privilege-escalation campaigns listed in threat actor data