CVE-2021-47477

HIGH
Published May 22, 2024 Modified Sep 24, 2025 CWE-787

Description

In the Linux kernel, the following vulnerability has been resolved: comedi: dt9812: fix DMA buffers on stack USB transfer buffers are typically mapped for DMA and must not be allocated on the stack or transfers will fail. Allocate proper transfer buffers in the various command helpers and return an error on short transfers instead of acting on random stack data. Note that this also fixes a stack info leak on systems where DMA is not used as 32 bytes are always sent to the device regardless of how short the command is.

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CVSS v3.1 Score

7.8
HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Weakness Type (CWE)

CWE-787 Out-of-bounds Write

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/20cebb8b620dc987e55ddc46801de986e081757e https://git.kernel.org/stable/c/365a346cda82f51d835c49136a00a9df8a78c7f2 https://git.kernel.org/stable/c/39ea61037ae78f14fa121228dd962ea3280eacf3 https://git.kernel.org/stable/c/3ac273d154d634e2034508a14db82a95d7ad12ed https://git.kernel.org/stable/c/3efb7af8ac437085b6c776e5b54830b149d86efe https://git.kernel.org/stable/c/536de747bc48262225889a533db6650731ab25d3 https://git.kernel.org/stable/c/786f5b03450454557ff858a8bead5d7c0cbf78d6 https://git.kernel.org/stable/c/8a52bc480992c7c9da3ebfea456af731f50a4b97 https://git.kernel.org/stable/c/a6af69768d5cb4b2528946d53be5fa19ade37723 https://git.kernel.org/stable/c/20cebb8b620dc987e55ddc46801de986e081757e https://git.kernel.org/stable/c/365a346cda82f51d835c49136a00a9df8a78c7f2 https://git.kernel.org/stable/c/39ea61037ae78f14fa121228dd962ea3280eacf3 https://git.kernel.org/stable/c/3ac273d154d634e2034508a14db82a95d7ad12ed https://git.kernel.org/stable/c/3efb7af8ac437085b6c776e5b54830b149d86efe https://git.kernel.org/stable/c/536de747bc48262225889a533db6650731ab25d3 https://git.kernel.org/stable/c/786f5b03450454557ff858a8bead5d7c0cbf78d6 https://git.kernel.org/stable/c/8a52bc480992c7c9da3ebfea456af731f50a4b97 https://git.kernel.org/stable/c/a6af69768d5cb4b2528946d53be5fa19ade37723

Frequently Asked Questions

What is CVE-2021-47477? +
In the Linux kernel, the following vulnerability has been resolved: comedi: dt9812: fix DMA buffers on stack USB transfer buffers are typically mapped for DMA and must not be allocated on the stack or transfers will fail. Allocate proper transfer buffers in the various command helpers and return an error on short transfers instead of acting on random stack data. Note that this also fixes a stack info leak on systems where DMA is not used as 32 bytes are always sent to the device regardless of how short the command is. It has a CVSS v3.1 base score of 7.8 (HIGH).
How severe is CVE-2021-47477? +
CVE-2021-47477 has a CVSS v3.1 score of 7.8 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.
What products are affected by CVE-2021-47477? +
CVE-2021-47477 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-2021-47477? +
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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