CVE-2021-46966

HIGH
Published Feb 27, 2024 Modified Dec 6, 2024 CWE-416

Description

In the Linux kernel, the following vulnerability has been resolved: ACPI: custom_method: fix potential use-after-free issue In cm_write(), buf is always freed when reaching the end of the function. If the requested count is less than table.length, the allocated buffer will be freed but subsequent calls to cm_write() will still try to access it. Remove the unconditional kfree(buf) at the end of the function and set the buf to NULL in the -EINVAL error path to match the rest of function.

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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-416 Use After Free

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/1d53ca5d131074c925ce38361fb0376d3bf7e394 https://git.kernel.org/stable/c/62dc2440ebb552aa0d7f635e1697e077d9d21203 https://git.kernel.org/stable/c/72814a94c38a33239793f7622cec6ace1e540c4b https://git.kernel.org/stable/c/8b04d57f30caf76649d0567551589af9a66ca9be https://git.kernel.org/stable/c/90575d1d9311b753cf1718f4ce9061ddda7dfd23 https://git.kernel.org/stable/c/a5b26a2e362f572d87e9fd35435680e557052a17 https://git.kernel.org/stable/c/b7a5baaae212a686ceb812c32fceed79c03c0234 https://git.kernel.org/stable/c/e483bb9a991bdae29a0caa4b3a6d002c968f94aa https://git.kernel.org/stable/c/f16737caf41fc06cfe6e49048becb09657074d4b https://git.kernel.org/stable/c/1d53ca5d131074c925ce38361fb0376d3bf7e394 https://git.kernel.org/stable/c/62dc2440ebb552aa0d7f635e1697e077d9d21203 https://git.kernel.org/stable/c/72814a94c38a33239793f7622cec6ace1e540c4b https://git.kernel.org/stable/c/8b04d57f30caf76649d0567551589af9a66ca9be https://git.kernel.org/stable/c/90575d1d9311b753cf1718f4ce9061ddda7dfd23 https://git.kernel.org/stable/c/a5b26a2e362f572d87e9fd35435680e557052a17 https://git.kernel.org/stable/c/b7a5baaae212a686ceb812c32fceed79c03c0234 https://git.kernel.org/stable/c/e483bb9a991bdae29a0caa4b3a6d002c968f94aa https://git.kernel.org/stable/c/f16737caf41fc06cfe6e49048becb09657074d4b

Frequently Asked Questions

What is CVE-2021-46966? +
In the Linux kernel, the following vulnerability has been resolved: ACPI: custom_method: fix potential use-after-free issue In cm_write(), buf is always freed when reaching the end of the function. If the requested count is less than table.length, the allocated buffer will be freed but subsequent calls to cm_write() will still try to access it. Remove the unconditional kfree(buf) at the end of the function and set the buf to NULL in the -EINVAL error path to match the rest of function. It has a CVSS v3.1 base score of 7.8 (HIGH).
How severe is CVE-2021-46966? +
CVE-2021-46966 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-2021-46966? +
CVE-2021-46966 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-2021-46966? +
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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