medium CVSS 5.5 EPSS <0.1%

CVE-2024-36930·Kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: spi: fix null pointer dereference within spi_sync If spi_sync() is called with the non-empty queue and the same spi_message is then reused, the complete callback for the message remains set while the context is cleared, leading to a null pointer dereference when the callback is invoked from spi_finalize_current_message(). With function inlining disabled, the call stack might look like this: _raw_spin_lock_irqsave from complete_with_flags+0x18/0x58 complete_with_flags from spi_complete+0x8/0xc spi_complete from spi_finalize_current_message+0xec/0x184 spi_finalize_current_message from spi_transfer_one_message+0x2a8/0x474 spi_transfer_one_message from __spi_pump_transfer_message+0x104/0x230 __spi_pump_transfer_message from __spi_transfer_message_noqueue+0x30/0xc4 __spi_transfer_message_noqueue from __spi_sync+0x204/0x248 __spi_sync from spi_sync+0x24/0x3c spi_sync from mcp251xfd_regmap_crc_read+0x124/0x28c [mcp251xfd] mcp251xfd_regmap_crc_read [mcp251xfd] from _regmap_raw_read+0xf8/0x154 _regmap_raw_read from _regmap_bus_read+0x44/0x70 _regmap_bus_read from _regmap_read+0x60/0xd8 _regmap_read from regmap_read+0x3c/0x5c regmap_read from mcp251xfd_alloc_can_err_skb+0x1c/0x54 [mcp251xfd] mcp251xfd_alloc_can_err_skb [mcp251xfd] from mcp251xfd_irq+0x194/0xe70 [mcp251xfd] mcp251xfd_irq [mcp251xfd] from irq_thread_fn+0x1c/0x78 irq_thread_fn from irq_thread+0x118/0x1f4 irq_thread from kthread+0xd8/0xf4 kthread from ret_from_fork+0x14/0x28 Fix this by also setting message->complete to NULL when the transfer is complete.

Severity
medium
Software
Kernel
Fixed in
6.8.10
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 4% 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.

Affected versions

From: 6.7

Until: 6.8.10

Fixed in: 6.8.10

How to fix this CVE

Update your Linux kernel to version 6.8.10 or later to resolve a null pointer dereference in the SPI subsystem that occurs when reusing SPI messages. This flaw can cause kernel crashes under specific SPI transfer patterns, particularly affecting CAN bus drivers and other SPI-dependent hardware. Apply the patch immediately to maintain system stability and prevent unexpected downtime.

sudo dnf update kernel kernel-devel

Defensia detects this vulnerability

How to check if you are affected

  1. Run `uname -r` to check the current kernel version; vulnerable versions are 6.7.x through 6.8.9
  2. Check if SPI devices are in use: `lsmod | grep spi` — look for spi_core, mcp251xfd, or similar SPI driver modules
  3. Search kernel logs for SPI-related crashes: `dmesg | grep -i 'spi\|null pointer\|oops'` or `journalctl -b | grep -i spi`
  4. Verify the patch is installed by confirming kernel version is 6.8.10 or later with `uname -r`

FAQ

What is CVE-2024-36930?

This vulnerability is a null pointer dereference in the Linux kernel's SPI (Serial Peripheral Interface) subsystem that occurs when an SPI message is reused while still queued, causing the completion callback to reference cleared context data and triggering a kernel crash.

Is CVE-2024-36930 being actively exploited?

No, this vulnerability is not listed in the CISA Known Exploited Vulnerabilities catalog and no public exploits are available. Exploitation requires local access and specific SPI driver conditions.

What versions of Kernel are affected by CVE-2024-36930?

Linux kernel versions 6.7.0 through 6.8.9 are affected. Kernel 6.8.10 and later contain the fix.

How do I check if my server is vulnerable to CVE-2024-36930?

Run `uname -r` and compare the output to the affected range (6.7.x to 6.8.9). If your version falls within this range and SPI devices are active, your system is vulnerable.

Does Defensia detect CVE-2024-36930?

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-2024-36930 will appear in your dashboard with remediation steps.

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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.
CVE-2026-52931CVSS 9.8In the Linux kernel, the following vulnerability has been resolved: batman-adv: tp_meter: avoid use of uninit sender vars batadv_tp_recv_ack() and batadv_tp_stop() are only valid for tp_vars in the BATADV_TP_SENDER role. When called with a BATADV_TP_RECEIVER role, it proceeds to read sender-only members that were never initialized, leading to undefined behavior. This can be triggered when a node that is currently acting as a receiver in an ongoing tp_meter session receives a malicious ACK packet. Guard against this by checking tp_vars->role immediately after the lookup and bailing out if it is not BATADV_TP_SENDER, before any of those members are accessed.
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References

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