CVE-2022-48790
CriticalCVSS 9.8Exploitation Probability (EPSS)
Elevated risk53th percentile - higher than 53% of all known CVEs
Summary
In the Linux kernel, a use-after-free vulnerability in the nvme driver during controller reset during load has been fixed. The issue occurs when the driver does not check controller readiness for AER submission, leading to a use-after-free condition observed with nvme-tcp.
Risk Assessment
The vulnerability could lead to system crashes or potentially arbitrary code execution in kernel context. An attacker could exploit this if they can trigger an NVMe controller reset.
Recommendation
Update the Linux kernel to a version with the fix. Also restrict access to NVMe devices to trusted users only.
Original NVD description (English source)
In the Linux kernel, the following vulnerability has been resolved: nvme: fix a possible use-after-free in controller reset during load Unlike .queue_rq, in .submit_async_event drivers may not check the ctrl readiness for AER submission. This may lead to a use-after-free condition that was observed with nvme-tcp. The race condition may happen in the following scenario: 1. driver executes its reset_ctrl_work 2. -> nvme_stop_ctrl - flushes ctrl async_event_work 3. ctrl sends AEN which is received by the host, which in turn schedules AEN handling 4. teardown admin queue (which releases the queue socket) 5. AEN processed, submits another AER, calling the driver to submit 6. driver attempts to send the cmd ==> use-after-free In order to fix that, add ctrl state check to validate the ctrl is actually able to accept the AER submission. This addresses the above race in controller resets because the driver during teardown should: 1. change ctrl state to RESETTING 2. flush async_event_work (as well as other async work elements) So after 1,2, any other AER command will find the ctrl state to be RESETTING and bail out without submitting the AER.