CVE-2022-50709: Linux

EPSS: 0.2% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: wifi: ath9k: avoid uninit memory read in ath9k_htc_rx_msg() syzbot is reporting uninit value at ath9k_htc_rx_msg() [1], for ioctl(USB_RAW_IOCTL_EP_WRITE) can call ath9k_hif_usb_rx_stream() with pkt_len = 0 but ath9k_hif_usb_rx_stream() uses __dev_alloc_skb(pkt_len + 32, GFP_ATOMIC) based on an assumption that pkt_len is valid. As a result, ath9k_hif_usb_rx_stream() allocates skb with uninitialized memory and ath9k_htc_rx_msg() is reading from uninitialized memory. Since bytes accessed by ath9k_htc_rx_msg() is not known until ath9k_htc_rx_msg() is called, it would be difficult to check minimal valid pkt_len at "if (pkt_len > 2 * MAX_RX_BUF_SIZE) {" line in ath9k_hif_usb_rx_stream(). We have two choices. One is to workaround by adding __GFP_ZERO so that ath9k_htc_rx_msg() sees 0 if pkt_len is invalid. The other is to let ath9k_htc_rx_msg() validate pkt_len before accessing. This patch chose the latter. Note that I'm not sure threshold condition is correct, for I can't find details on possible packet length used by this protocol.

Affected products

• Linux Linux: from 2.6.35, before 4.14.296 (fixed in 4.14.296); from 4.15, before 4.19.262 (fixed in 4.19.262); from 4.20, before 5.4.220 (fixed in 5.4.220); from 5.5, before 5.10.150 (fixed in 5.10.150); from 5.11, before 5.15.75 (fixed in 5.15.75); from 5.16, before 5.19.17 (fixed in 5.19.17); …

Published 2025-12-24. Last modified 2026-06-17.