CVE-2026-53231

What the bug is

We don't have support for PHY-driver SFP cages with the genphy code. On top of that, it was found by sashiko that running sfp_bus_add_upstream() for genphy deadlocks, as for genphy the PHY probing runs under RTNL, which isn't the case for non-genphy drivers. This problem was reproduced, and does lead to a deadlock on RTNL. Before the blamed commit, the phy_sfp_probe() call was made by individual PHY drivers, so there was no way to get to the SFP probing path when using genphy. Let's therefore only run phy_sfp_probe when not using genphy.

Where it lives

The fix touches these files. If the subsystem is one you do not use, the practical exposure is lower, though the package is still the vulnerable one.

drivers/net/phy/phy_device.c

What this is

ETHERNET PHY LIBRARYMAINTAINERS section matched on drivers/net/phy/ · netdev@vger.kernel.org · Maintained

Kernel module

libphy

Check it on the machine

grep -w CONFIG_PHYLIB /boot/config-$(uname -r)

Reads the booted kernel's own configuration, on the machine and nowhere else. =y is built in, =m is a module, and an is not set line means the code is not there.

lsmod | grep -w libphy

Prints a line if that module is loaded right now, and nothing if it is not. One that is not loaded can still be loaded later by anything that needs it.

Show whether Debian builds this, per release

Debian builds this, but not on every flavour. At least one release below builds the code on some of its kernel flavours and not on others, so the answer depends on the architecture and flavour installed.

• bookworm, trixieMnot built on amd64/cloud-amd64
• forky, sidBnot built on amd64/cloud-amd64

M

a module where it is built at all; some flavours do not build it

B

built in on some, a module on others, absent on the rest

Build switch

CONFIG_PHYLIB

From the configuration Debian publishes for every kernel flavour it builds. It covers only the architectures Debian ships a linux-config package for, and nothing about a kernel you built yourself. Debian's own status above stays authoritative about the source package.MAINTAINERS kbuild Makefiles Debian linux-config packages

Signals

Published

2026-06-25 (4 months ago)source

CVSS

no vector published, unrated

Attack vector

not published

EPSS

0.08%, higher than 0.2% of all CVEssource

CISA KEV

not listedthe KEV catalogue

Debian urgency

unimportantsource

Subsystem

drivers/net

Upstream fixes

The versions the CNA records as introducing and fixing this, and the commit for each. source

Introduced	Fixed in	Commit
7.0	7.0.13	ef8d739eee6f
7.0	7.1	5a0082ec20a0