CVE-2025-39890 wifi: ath12k: fix memory leak in ath12k_service_ready_ext_event
A memory leak in the ath12k WiFi driver allows attackers to cause a denial of service by exhausting kernel memory.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2025-39890?
CVE-2025-39890 is a medium-severity denial of service vulnerability in Linux kernel, published on 24 Sep 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
wifi: ath12k: fix memory leak in ath12k_service_ready_ext_event
Currently, in ath12k_service_ready_ext_event(), svc_rdy_ext.mac_phy_caps is not freed in the failure case, causing a memory leak. The following trace is observed in kmemleak:
unreferenced object 0xffff8b3eb5789c00 (size 1024): comm "softirq", pid 0, jiffies 4294942577 hex dump (first 32 bytes): 00 00 00 00 01 00 00 00 00 00 00 00 7b 00 00 10 ............{... 01 00 00 00 00 00 00 00 01 00 00 00 1f 38 00 00 .............8.. backtrace (crc 44e1c357): __kmalloc_noprof+0x30b/0x410 ath12k_wmi_mac_phy_caps_parse+0x84/0x100 [ath12k] ath12k_wmi_tlv_iter+0x5e/0x140 [ath12k] ath12k_wmi_svc_rdy_ext_parse+0x308/0x4c0 [ath12k] ath12k_wmi_tlv_iter+0x5e/0x140 [ath12k] ath12k_service_ready_ext_event.isra.0+0x44/0xd0 [ath12k] ath12k_wmi_op_rx+0x2eb/0xd70 [ath12k] ath12k_htc_rx_completion_handler+0x1f4/0x330 [ath12k] ath12k_ce_recv_process_cb+0x218/0x300 [ath12k] ath12k_pci_ce_workqueue+0x1b/0x30 [ath12k] process_one_work+0x219/0x680 bh_worker+0x198/0x1f0 tasklet_action+0x13/0x30 handle_softirqs+0xca/0x460 __irq_exit_rcu+0xbe/0x110 irq_exit_rcu+0x9/0x30
Free svc_rdy_ext.mac_phy_caps in the error case to fix this memory leak.
Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.4.1-00199-QCAHKSWPL_SILICONZ-1
Weakness: CWE-401
Which versions are affected by CVE-2025-39890?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2025-39890?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2025-39890 being exploited?
There is no known exploitation of CVE-2025-39890 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2025-39890, DEBIAN-CVE-2025-39890, GHSA-5cg2-hfc8-xx57, ROOT-OS-UBUNTU-2404-CVE-2025-39890, UBUNTU-CVE-2025-39890.