CVE-2022-50709

CVE-2022-50709 is a security vulnerability that is still awaiting full analysis and scoring. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Description

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.

Frequently asked questions

What is CVE-2022-50709?
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.
Is CVE-2022-50709 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (8th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2022-50709?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2022-50709 have an EU (EUVD) identifier?
Yes. CVE-2022-50709 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-205175.
When was CVE-2022-50709 published?
CVE-2022-50709 was published on 2025-12-24 and last updated on 2026-06-17.

References