high CVSS 7.8 EPSS <0.1%

CVE-2022-49470·Kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: btmtksdio: fix use-after-free at btmtksdio_recv_event We should not access skb buffer data anymore after hci_recv_frame was called. [ 39.634809] BUG: KASAN: use-after-free in btmtksdio_recv_event+0x1b0 [ 39.634855] Read of size 1 at addr ffffff80cf28a60d by task kworker [ 39.634962] Call trace: [ 39.634974] dump_backtrace+0x0/0x3b8 [ 39.634999] show_stack+0x20/0x2c [ 39.635016] dump_stack_lvl+0x60/0x78 [ 39.635040] print_address_description+0x70/0x2f0 [ 39.635062] kasan_report+0x154/0x194 [ 39.635079] __asan_report_load1_noabort+0x44/0x50 [ 39.635099] btmtksdio_recv_event+0x1b0/0x1c4 [ 39.635129] btmtksdio_txrx_work+0x6cc/0xac4 [ 39.635157] process_one_work+0x560/0xc5c [ 39.635177] worker_thread+0x7ec/0xcc0 [ 39.635195] kthread+0x2d0/0x3d0 [ 39.635215] ret_from_fork+0x10/0x20 [ 39.635247] Allocated by task 0: [ 39.635260] (stack is not available) [ 39.635281] Freed by task 2392: [ 39.635295] kasan_save_stack+0x38/0x68 [ 39.635319] kasan_set_track+0x28/0x3c [ 39.635338] kasan_set_free_info+0x28/0x4c [ 39.635357] ____kasan_slab_free+0x104/0x150 [ 39.635374] __kasan_slab_free+0x18/0x28 [ 39.635391] slab_free_freelist_hook+0x114/0x248 [ 39.635410] kfree+0xf8/0x2b4 [ 39.635427] skb_free_head+0x58/0x98 [ 39.635447] skb_release_data+0x2f4/0x410 [ 39.635464] skb_release_all+0x50/0x60 [ 39.635481] kfree_skb+0xc8/0x25c [ 39.635498] hci_event_packet+0x894/0xca4 [bluetooth] [ 39.635721] hci_rx_work+0x1c8/0x68c [bluetooth] [ 39.635925] process_one_work+0x560/0xc5c [ 39.635951] worker_thread+0x7ec/0xcc0 [ 39.635970] kthread+0x2d0/0x3d0 [ 39.635990] ret_from_fork+0x10/0x20 [ 39.636021] The buggy address belongs to the object at ffffff80cf28a600 which belongs to the cache kmalloc-512 of size 512 [ 39.636039] The buggy address is located 13 bytes inside of 512-byte region [ffffff80cf28a600, ffffff80cf28a800)

Severity
high
Software
Kernel
Fixed in
5.18.3
Published

How likely is exploitation

FIRST's Exploit Prediction Scoring System puts the probability of this CVE being exploited in the next 30 days at <0.1% — higher than 11% of all published CVEs. EPSS is an independent forecast of exploitation, not a severity rating: it says nothing about how much damage a successful attack does, which is what a CVSS score measures.

Read the two together. CVE-2022-49470 scores 7.8 on CVSS, so a successful attack would be serious — but at <0.1%, almost nobody is currently attempting it. That is a different situation from a flaw under mass exploitation, and it is usually the difference between patching on your next maintenance window and patching tonight.

Affected versions

From: 5.18

Until: 5.18.3

Fixed in: 5.18.3

How to fix this CVE

Update your Linux kernel to version 5.18.3 or later to resolve this use-after-free vulnerability in the Bluetooth SDIO driver. This memory safety issue can cause kernel crashes when the btmtksdio driver processes Bluetooth events. Apply the patch immediately to systems running kernel versions 5.18.0 through 5.18.2 that depend on Bluetooth functionality.

sudo dnf update kernel kernel-devel

Defensia detects this vulnerability

How to check if you are affected

  1. Check your kernel version: uname -r
  2. Verify if the vulnerable kernel range is installed: grep -i version /proc/version | awk '{print $3}' and compare against 5.18.0-5.18.2
  3. Confirm Bluetooth SDIO driver is loaded: lsmod | grep btmtksdio
  4. After patching, verify the new kernel version: uname -r should show 5.18.3 or higher
  5. Check kernel logs for use-after-free errors: dmesg | grep -i 'use-after-free\|btmtksdio\|kasan'

FAQ

What is CVE-2022-49470?

CVE-2022-49470 is a use-after-free memory vulnerability in the Linux kernel's Bluetooth SDIO driver (btmtksdio). The driver incorrectly accesses SKB (socket buffer) data after passing it to hci_recv_frame(), which frees the buffer, resulting in a use-after-free condition that can crash the kernel.

Is CVE-2022-49470 being actively exploited?

No, CVE-2022-49470 is not listed on the CISA KEV catalog and has no known public exploits. However, it remains a critical stability issue for systems with Bluetooth SDIO hardware.

What versions of Kernel are affected by CVE-2022-49470?

Linux kernel versions 5.18.0 through 5.18.2 are affected. The vulnerability was fixed in kernel 5.18.3 and later stable releases.

How do I check if my server is vulnerable to CVE-2022-49470?

Run 'uname -r' and check if your kernel version falls within 5.18.0-5.18.2, then verify Bluetooth SDIO hardware is present with 'lsmod | grep btmtksdio'. If both conditions are true, your system is vulnerable.

Does Defensia detect CVE-2022-49470?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If the Linux kernel is installed on a monitored server, CVE-2022-49470 will appear in your dashboard with remediation steps.

Related Kernel CVEs

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CVE-2026-64268CVSS 9.8In the Linux kernel, the following vulnerability has been resolved: RDMA/siw: bound Read Response placement to the RREAD length In drivers/infiniband/sw/siw/siw_qp_rx.c, siw_proc_rresp() places each inbound Read Response DDP segment at sge->laddr + wqe->processed and then accumulates wqe->processed, but it never checks the running total against the sink buffer length on continuation segments. siw_check_sge() resolves and validates the sink memory only on the first fragment (the if (!*mem) branch), and siw_rresp_check_ntoh() compares the cumulative length against wqe->bytes only on the final segment (the !frx->more_ddp_segs guard). A connected siw peer that answers an outstanding RREAD with Read Response segments that keep the DDP Last flag clear, carrying more total payload than the RREAD requested, drives wqe->processed past the validated sink buffer; the next siw_rx_data() call writes out of bounds at sge->laddr + wqe->processed. siw runs iWARP over ordinary routable TCP, so the peer is the remote end of an established RDMA connection and needs no local privilege. Bound every segment before placement, exactly as siw_proc_send() and siw_proc_write() already do for their tagged and untagged paths, and terminate the connection with a base-or-bounds DDP error when the Read Response would overrun the sink buffer. This is the second receive-path length fix for this file. A separate change rejects an MPA FPDU length that underflows the per-fragment remainder in the header decode; that guard does not cover this case, because here each individual segment length is self-consistent and only the accumulated placement offset overruns the buffer.
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CVE-2026-53384CVSS 9.8In the Linux kernel, the following vulnerability has been resolved: serial: 8250_dw: unregister 8250 port if clk_notifier_register() fails dw8250_probe() registers the 8250 port via serial8250_register_8250_port() and then, if the device has a clock, registers a clock notifier. If clk_notifier_register() fails, probe returns the error but leaves the 8250 port registered. The matching serial8250_unregister_port() lives in dw8250_remove(), which is not called when probe fails, so the port slot stays occupied until the device is rebound or the system is rebooted. The devm-allocated driver data is freed while the port still references it (via the saved private_data and serial_in/serial_out callbacks), so any access to that port slot before a rebind is a use-after-free hazard. Unregister the port on the clk_notifier_register() error path.

References

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