CVE-2026-97516
kernel: wifi: rtw88: Add NULL check for chip->edcca_th in rtw_fw_adaptivity_result()
Severity
LowRed Hat Product Security
CVSS 3.1
Review impact separately from score.
Published · September 24, 2026
Updated · October 18, 2026
Description
A flaw was found in the Linux kernel's rtw88 wireless driver. The driver fails to verify whether certain hardware configuration settings exist before accessing them during firmware adaptivity processing. On systems equipped with specific wireless chipsets, this flaw triggers a null pointer dereference that crashes the kernel, resulting in a Denial of Service (DoS).
Statement
A low-impact NULL pointer dereference flaw was found in the Linux kernel rtw88 wireless driver. The rtw_fw_adaptivity_result() function in fw.c dereferences rtwdev->chip->edcca_th without first verifying that the pointer is defined. On systems using wireless chipsets whose chip information does not define edcca_th, such as the Realtek 8821CE, processing a firmware adaptivity result triggers a kernel oops, resulting in a local denial of service. Chipsets that do define edcca_th, such as the 8822CE, are not affected by this issue. Red Hat Product Security has rated this flaw as low impact because triggering it requires local access to a system running the affected driver on such hardware and the consequence is limited to loss of availability, with no impact to confidentiality or integrity. Red Hat Enterprise Linux 6 and 7 ELS streams and RHEL 8.4 are not affected because the vulnerable code is not present in those kernels. For the affected Red Hat Enterprise Linux, Red Hat In-Vehicle OS, and OpenShift Container Platform streams, the fix is currently deferred in line with the low impact rating, and the residual risk is limited to a kernel crash (denial of service) on systems equipped with the affected Realtek wireless chipsets. Although the Red Hat CVSS 3.1 base score is 5.5 (Moderate), the overall impact has been assessed as low based on the local attack vector and availability-only consequence. The upstream fix adds a NULL check for edcca_th at the entry of rtw_fw_adaptivity_result(), preventing the kernel oops.
CVSS score applicability
The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.
Mitigation
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
CVSS / CWE
CVSS 3.1 · 5.5CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
CWE-476 · NULL Pointer Dereference