CVE-2021-47476

MEDIUM
Published May 22, 2024 Modified Apr 2, 2025 CWE-476

Description

In the Linux kernel, the following vulnerability has been resolved: comedi: ni_usb6501: fix NULL-deref in command paths The driver uses endpoint-sized USB transfer buffers but had no sanity checks on the sizes. This can lead to zero-size-pointer dereferences or overflowed transfer buffers in ni6501_port_command() and ni6501_counter_command() if a (malicious) device has smaller max-packet sizes than expected (or when doing descriptor fuzz testing). Add the missing sanity checks to probe().

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CVSS v3.1 Score

4.6
MEDIUM
CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Weakness Type (CWE)

CWE-476 CWE-476

Affected Products

Vendor Product
linux linux_kernel
linux linux_kernel
linux linux_kernel
linux linux_kernel
linux linux_kernel
linux linux_kernel
linux linux_kernel
linux linux_kernel

References

Advisories & Patches

https://git.kernel.org/stable/c/4a9d43cb5d5f39fa39fc1da438517004cc95f7ea https://git.kernel.org/stable/c/58478143771b20ab219937b1c30a706590a59224 https://git.kernel.org/stable/c/907767da8f3a925b060c740e0b5c92ea7dbec440 https://git.kernel.org/stable/c/aa39738423503825625853b643b9e99d11c23816 https://git.kernel.org/stable/c/b0156b7c9649d8f55a2ce3d3258509f1b2a181c3 https://git.kernel.org/stable/c/bc51111bf6e8e7b6cc94b133e4c291273a16acd1 https://git.kernel.org/stable/c/d6a727a681a39ae4f73081a9bedb45d14f95bdd1 https://git.kernel.org/stable/c/df7b1238f3b599a0b9284249772cdfd1ea83a632 https://git.kernel.org/stable/c/ef143dc0c3defe56730ecd3a9de7b3e1d7e557c1 https://git.kernel.org/stable/c/4a9d43cb5d5f39fa39fc1da438517004cc95f7ea https://git.kernel.org/stable/c/58478143771b20ab219937b1c30a706590a59224 https://git.kernel.org/stable/c/907767da8f3a925b060c740e0b5c92ea7dbec440 https://git.kernel.org/stable/c/aa39738423503825625853b643b9e99d11c23816 https://git.kernel.org/stable/c/b0156b7c9649d8f55a2ce3d3258509f1b2a181c3 https://git.kernel.org/stable/c/bc51111bf6e8e7b6cc94b133e4c291273a16acd1 https://git.kernel.org/stable/c/d6a727a681a39ae4f73081a9bedb45d14f95bdd1 https://git.kernel.org/stable/c/df7b1238f3b599a0b9284249772cdfd1ea83a632 https://git.kernel.org/stable/c/ef143dc0c3defe56730ecd3a9de7b3e1d7e557c1

Frequently Asked Questions

What is CVE-2021-47476? +
In the Linux kernel, the following vulnerability has been resolved: comedi: ni_usb6501: fix NULL-deref in command paths The driver uses endpoint-sized USB transfer buffers but had no sanity checks on the sizes. This can lead to zero-size-pointer dereferences or overflowed transfer buffers in ni6501_port_command() and ni6501_counter_command() if a (malicious) device has smaller max-packet sizes than expected (or when doing descriptor fuzz testing). Add the missing sanity checks to probe(). It has a CVSS v3.1 base score of 4.6 (MEDIUM).
How severe is CVE-2021-47476? +
CVE-2021-47476 has a CVSS v3.1 score of 4.6 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.
What products are affected by CVE-2021-47476? +
CVE-2021-47476 affects products from linux, specifically: linux_kernel. Check the affected products table above for specific version ranges.
How do I check if I'm vulnerable to CVE-2021-47476? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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