CVE-2023-53576
BaseFortify
Publication date: 2025-10-04
Last updated on: 2026-03-23
Assigner: kernel.org
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| linux | linux_kernel | From 6.2 (inc) to 6.3.4 (inc) |
| linux | linux_kernel | 6.3.0-rc5lblk |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-476 | The product dereferences a pointer that it expects to be valid but is NULL. |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
This vulnerability in the Linux kernel's null_blk driver occurs because the device queue mode setting from configfs is not properly checked. Without the patch, setting the queue mode to 1 leads to kernel oops (crashes) due to the use of a legacy I/O path that is not allowed. The fix ensures that the queue mode is validated and an error is returned if the legacy mode is set, preventing the kernel crash.
How can this vulnerability impact me? :
If exploited, this vulnerability can cause the Linux kernel to crash (kernel oops), leading to system instability or denial of service. This can disrupt normal operations on systems using the null_blk driver with misconfigured queue mode settings.
How can this vulnerability be detected on my network or system? Can you suggest some commands?
This vulnerability can be detected by checking if the null_blk device queue mode is set to 1 from configfs, which causes kernel oops. You can attempt to reproduce the issue using the following commands: modprobe null_blk nr_devices=0 mkdir -p /config/nullb/nullb0 echo 1 > /config/nullb/nullb0/memory_backed echo 4096 > /config/nullb/nullb0/blocksize echo 20480 > /config/nullb/nullb0/size echo 1 > /config/nullb/nullb0/queue_mode echo 1 > /config/nullb/nullb0/power If the system crashes or shows kernel oops related to null_blk, the vulnerability is present.
What immediate steps should I take to mitigate this vulnerability?
Immediate mitigation involves ensuring that the device queue mode is not set to 1 in configfs for null_blk devices, as legacy I/O path is not allowed and causes kernel oops. Applying the patch that adds validation in null_validate_conf() to check queue mode and reject NULL_Q_RQ is necessary to prevent the issue.