CVE-2026-97516

What the bug is

It was recently reported that rtw_fw_adaptivity_result() in fw.c dereferences rtwdev->chip->edcca_th without a NULL check. The issue is that devices with the 8821CE chip don't define edcca_th in their chip info. As a result, when rtw_fw_adaptivity_result() tries to dereference it, the kernel triggers an oops. Add a NULL check for edcca_th before dereferencing it in rtw_fw_adaptivity_result() in fw.c. Placing the check at the function entry avoids logging any garbage values. This change does not address the root cause for this behavior, but it prevents the NULL dereference and the resulting oops while a more permanent solution is developed. Tested on a 8822CE chip which defines edcca_th, so this issue is not present on it, but it still uses this driver and I can verify there are no regressions.

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/wireless/realtek/rtw88/fw.c

What this is

REALTEK WIRELESS DRIVER (rtw88)MAINTAINERS section matched on drivers/net/wireless/realtek/rtw88/ · linux-wireless@vger.kernel.org · Maintained

Kernel module

rtw88_core

Check it on the machine

grep -wE 'CONFIG_RTW88|CONFIG_RTW88_CORE|CONFIG_WLAN|CONFIG_WLAN_VENDOR_REALTEK' /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 rtw88_core

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.

• bookwormMnot built on amd64/cloud-amd64, arm64/cloud-arm64
• trixie, forky, sidMnot built on amd64/cloud-amd64, arm64/cloud-arm64, s390x/s390x
• bookworm · linux-6.12Mnot built on amd64/cloud-amd64, arm64/cloud-arm64

M

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

Build switches

CONFIG_RTW88, CONFIG_RTW88_CORE, CONFIG_WLAN, CONFIG_WLAN_VENDOR_REALTEK

Reads as

all on means the file is compiled; any one off means it is not.

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

2026-09-24 (24 days ago)source

CVSS

no vector published, unrated

Attack vector

not published

EPSS

0.16%, higher than 4.4% of all CVEssource

CISA KEV

not listedthe KEV catalogue

Debian urgency

not yet assignedsource

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
5.16	6.1.189	a8cdb18ef80d
5.16	6.6.158	0b58a5ac9170
5.16	6.12.111	6fa23cafaf30
5.16	6.18.53	1d1f250432cd
5.16	7.2	d5e6f353ce1e

Debian advisories