CVE-2026-98711

/// Technical description

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

wifi: cw1200: fix TX padding OOB read leaking heap data to device

The TX path rounds the transfer size up to the bus alignment

(align_size(), up to 511 bytes for SDIO, 1 byte for SPI) but sends

the padded length straight from the frame buffer, which has no room

reserved for the padding. cw1200_data_write() therefore reads past

the end of the frame and the bus transfer carries those bytes to the

device. A bogus device can collect up to 511 bytes of kernel heap

data per TX frame.

The RX path does not have this problem: it allocates the skb with

the aligned length (alloc_len) before reading.

Compute the exact padding with the bus align_size() callback, make

sure queued TX frames have tailroom for it, and zero the padding

bytes before the transfer so nothing past the frame is exposed.

This is not expected to change driver behavior on most cases: frame

contents and transfer sizes are unchanged, only the content of th

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References