CVE-2021-47509

MEDIUM
Published May 24, 2024 Modified Sep 29, 2025

Description

In the Linux kernel, the following vulnerability has been resolved: ALSA: pcm: oss: Limit the period size to 16MB Set the practical limit to the period size (the fragment shift in OSS) instead of a full 31bit; a too large value could lead to the exhaust of memory as we allocate temporary buffers of the period size, too. As of this patch, we set to 16MB limit, which should cover all use cases.

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CVSS v3.1 Score

5.5
MEDIUM
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

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
linux linux_kernel
linux linux_kernel
linux linux_kernel

References

Advisories & Patches

https://git.kernel.org/stable/c/2e54cf6794bf82a54aaefc78da13819aea9cd28a https://git.kernel.org/stable/c/35a3e511032146941085f87dd9fb5b82ea5c00a2 https://git.kernel.org/stable/c/76f19e4cbb548e28547f8c328aa0bfb3a10222d3 https://git.kernel.org/stable/c/8839c8c0f77ab8fc0463f4ab8b37fca3f70677c2 https://git.kernel.org/stable/c/ad45babf7886e7a212ee1d5eda9ef49f696db43c https://git.kernel.org/stable/c/b02a41eebcc36d4f07196780f2e165ca2c499257 https://git.kernel.org/stable/c/be55f306396cd62c6889286a7194fd8b53363aeb https://git.kernel.org/stable/c/d1bb703ad050de9095f10b2d3416c32921ac6bcc https://git.kernel.org/stable/c/2e54cf6794bf82a54aaefc78da13819aea9cd28a https://git.kernel.org/stable/c/35a3e511032146941085f87dd9fb5b82ea5c00a2 https://git.kernel.org/stable/c/76f19e4cbb548e28547f8c328aa0bfb3a10222d3 https://git.kernel.org/stable/c/8839c8c0f77ab8fc0463f4ab8b37fca3f70677c2 https://git.kernel.org/stable/c/ad45babf7886e7a212ee1d5eda9ef49f696db43c https://git.kernel.org/stable/c/b02a41eebcc36d4f07196780f2e165ca2c499257 https://git.kernel.org/stable/c/be55f306396cd62c6889286a7194fd8b53363aeb https://git.kernel.org/stable/c/d1bb703ad050de9095f10b2d3416c32921ac6bcc

Frequently Asked Questions

What is CVE-2021-47509? +
In the Linux kernel, the following vulnerability has been resolved: ALSA: pcm: oss: Limit the period size to 16MB Set the practical limit to the period size (the fragment shift in OSS) instead of a full 31bit; a too large value could lead to the exhaust of memory as we allocate temporary buffers of the period size, too. As of this patch, we set to 16MB limit, which should cover all use cases. It has a CVSS v3.1 base score of 5.5 (MEDIUM).
How severe is CVE-2021-47509? +
CVE-2021-47509 has a CVSS v3.1 score of 5.5 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-2021-47509? +
CVE-2021-47509 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-2021-47509? +
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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