high CVSS 7.8 EPSS <0.1%

CVE-2022-48867·Kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: dmaengine: idxd: Prevent use after free on completion memory On driver unload any pending descriptors are flushed at the time the interrupt is freed: idxd_dmaengine_drv_remove() -> drv_disable_wq() -> idxd_wq_free_irq() -> idxd_flush_pending_descs(). If there are any descriptors present that need to be flushed this flow triggers a "not present" page fault as below: BUG: unable to handle page fault for address: ff391c97c70c9040 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page The address that triggers the fault is the address of the descriptor that was freed moments earlier via: drv_disable_wq()->idxd_wq_free_resources() Fix the use after free by freeing the descriptors after any possible usage. This is done after idxd_wq_reset() to ensure that the memory remains accessible during possible completion writes by the device.

Severity
high
Software
Kernel
Fixed in
6.1.8
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 3% 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-2022-48867 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: 5.19

Until: 6.1.8

Fixed in: 6.1.8

How to fix this CVE

Update your Linux kernel to version 6.1.8 or later to resolve a use-after-free vulnerability in the dmaengine IDXD driver that occurs during driver unload. This vulnerability can cause kernel page faults when pending DMA descriptors are accessed after their memory has been freed. Apply the patch immediately to systems running kernel versions 5.19 through 6.1.7.

sudo dnf update kernel kernel-devel

Defensia detects this vulnerability

How to check if you are affected

  1. Check installed kernel version: uname -r — if the output shows a version between 5.19 and 6.1.7, your system is vulnerable
  2. Verify IDXD driver is present: lsmod | grep idxd — if idxd module is loaded, the vulnerability is exploitable on this system
  3. Search kernel logs for page faults during driver operations: dmesg | grep -i 'page fault' | grep -i 'idxd\|dmaengine' — look for 'not-present page' errors
  4. Confirm the fix: uname -r should show version 6.1.8 or later after patching; verify with grep EXTRAVERSION /usr/src/linux-headers-$(uname -r)/.config

FAQ

What is CVE-2022-48867?

CVE-2022-48867 is a use-after-free vulnerability in the Linux kernel's dmaengine IDXD driver that occurs when pending DMA descriptors are flushed during driver unload, causing the driver to access memory that has already been freed, leading to a kernel panic.

Is CVE-2022-48867 being actively exploited?

No, CVE-2022-48867 is not listed in the CISA Known Exploited Vulnerabilities catalog and no public exploits are available. However, it can be triggered by unprivileged local users with access to driver unload operations.

What versions of Kernel are affected by CVE-2022-48867?

Linux kernel versions 5.19 through 6.1.7 are vulnerable. The vulnerability was fixed in kernel 6.1.8 and later versions.

How do I check if my server is vulnerable to CVE-2022-48867?

Run `uname -r` to check your kernel version — if it reports a version between 5.19 and 6.1.7, you are vulnerable. Additionally, confirm the IDXD driver is present with `lsmod | grep idxd`.

Does Defensia detect CVE-2022-48867?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If the Linux kernel is installed on a monitored server running versions 5.19-6.1.7, CVE-2022-48867 will appear in your dashboard with remediation steps.

Related Kernel CVEs

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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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