CVE-2025-38606

CVE-2025-38606 is a medium-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-476.

Key facts

Description

In the Linux kernel, the following vulnerability has been resolved: wifi: ath12k: Avoid accessing uninitialized arvif->ar during beacon miss During beacon miss handling, ath12k driver iterates over active virtual interfaces (vifs) and attempts to access the radio object (ar) via arvif->deflink->ar. However, after commit aa80f12f3bed ("wifi: ath12k: defer vdev creation for MLO"), arvif is linked to a radio only after vdev creation, typically when a channel is assigned or a scan is requested. For P2P capable devices, a default P2P interface is created by wpa_supplicant along with regular station interfaces, these serve as dummy interfaces for P2P-capable stations, lack an associated netdev and initiate frequent scans to discover neighbor p2p devices. When a scan is initiated on such P2P vifs, driver selects destination radio (ar) based on scan frequency, creates a scan vdev, and attaches arvif to the radio. Once the scan completes or is aborted, the scan vdev is deleted, detaching arvif from the radio and leaving arvif->ar uninitialized. While handling beacon miss for station interfaces, P2P interface is also encountered in the vif iteration and ath12k_mac_handle_beacon_miss_iter() tries to dereference the uninitialized arvif->deflink->ar. Fix this by verifying that vdev is created for the arvif before accessing its ar during beacon miss handling and similar vif iterator callbacks. ========================================================================== wlp6s0: detected beacon loss from AP (missed 7 beacons) - probing KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017] CPU: 5 UID: 0 PID: 0 Comm: swapper/5 Not tainted 6.16.0-rc1-wt-ath+ #2 PREEMPT(full) RIP: 0010:ath12k_mac_handle_beacon_miss_iter+0xb5/0x1a0 [ath12k] Call Trace: __iterate_interfaces+0x11a/0x410 [mac80211] ieee80211_iterate_active_interfaces_atomic+0x61/0x140 [mac80211] ath12k_mac_handle_beacon_miss+0xa1/0xf0 [ath12k] ath12k_roam_event+0x393/0x560 [ath12k] ath12k_wmi_op_rx+0x1486/0x28c0 [ath12k] ath12k_htc_process_trailer.isra.0+0x2fb/0x620 [ath12k] ath12k_htc_rx_completion_handler+0x448/0x830 [ath12k] ath12k_ce_recv_process_cb+0x549/0x9e0 [ath12k] ath12k_ce_per_engine_service+0xbe/0xf0 [ath12k] ath12k_pci_ce_workqueue+0x69/0x120 [ath12k] process_one_work+0xe3a/0x1430 Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.4.1-00199-QCAHKSWPL_SILICONZ-1 Tested-on: WCN7850 hw2.0 PCI WLAN.HMT.1.1.c5-00284.1-QCAHMTSWPL_V1.0_V2.0_SILICONZ-3

Frequently asked questions

What is CVE-2025-38606?
In the Linux kernel, the following vulnerability has been resolved: wifi: ath12k: Avoid accessing uninitialized arvif->ar during beacon miss During beacon miss handling, ath12k driver iterates over active virtual interfaces (vifs) and attempts to access the radio object (ar) via arvif->deflink->ar. However, after commit aa80f12f3bed ("wifi: ath12k: defer vdev creation for MLO"), arvif is linked to a radio only after vdev creation, typically when a channel is assigned or a scan is requested. For P2P capable devices, a default P2P interface is created by wpa_supplicant along with regular station interfaces, these serve as dummy interfaces for P2P-capable stations, lack an associated netdev and initiate frequent scans to discover neighbor p2p devices. When a scan is initiated on such P2P vifs, driver selects destination radio (ar) based on scan frequency, creates a scan vdev, and attaches arvif to the radio. Once the scan completes or is aborted, the scan vdev is deleted, detaching arvif from the radio and leaving arvif->ar uninitialized. While handling beacon miss for station interfaces, P2P interface is also encountered in the vif iteration and ath12k_mac_handle_beacon_miss_iter() tries to dereference the uninitialized arvif->deflink->ar. Fix this by verifying that vdev is created for the arvif before accessing its ar during beacon miss handling and similar vif iterator callbacks. ========================================================================== wlp6s0: detected beacon loss from AP (missed 7 beacons) - probing KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017] CPU: 5 UID: 0 PID: 0 Comm: swapper/5 Not tainted 6.16.0-rc1-wt-ath+ #2 PREEMPT(full) RIP: 0010:ath12k_mac_handle_beacon_miss_iter+0xb5/0x1a0 [ath12k] Call Trace: __iterate_interfaces+0x11a/0x410 [mac80211] ieee80211_iterate_active_interfaces_atomic+0x61/0x140 [mac80211] ath12k_mac_handle_beacon_miss+0xa1/0xf0 [ath12k] ath12k_roam_event+0x393/0x560 [ath12k] ath12k_wmi_op_rx+0x1486/0x28c0 [ath12k] ath12k_htc_process_trailer.isra.0+0x2fb/0x620 [ath12k] ath12k_htc_rx_completion_handler+0x448/0x830 [ath12k] ath12k_ce_recv_process_cb+0x549/0x9e0 [ath12k] ath12k_ce_per_engine_service+0xbe/0xf0 [ath12k] ath12k_pci_ce_workqueue+0x69/0x120 [ath12k] process_one_work+0xe3a/0x1430 Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.4.1-00199-QCAHKSWPL_SILICONZ-1 Tested-on: WCN7850 hw2.0 PCI WLAN.HMT.1.1.c5-00284.1-QCAHMTSWPL_V1.0_V2.0_SILICONZ-3
How severe is CVE-2025-38606?
CVE-2025-38606 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2025-38606 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (4th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-38606?
CVE-2025-38606 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-38606?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-38606 have an EU (EUVD) identifier?
Yes. CVE-2025-38606 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-27931.
When was CVE-2025-38606 published?
CVE-2025-38606 was published on 2025-08-19 and last updated on 2026-06-17.

References

Affected products (1)

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