CVE-2021-47123: linux kernel Double Free — Fix

Description

In the Linux kernel, the following vulnerability has been resolved: io_uring: fix ltout double free on completion race Always remove linked timeout on io_link_timeout_fn() from the master request link list, otherwise we may get use-after-free when first io_link_timeout_fn() puts linked timeout in the fail path, and then will be found and put on master's free.

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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-415 CWE-415

CWE-416 Use After Free

Affected Products

Vendor	Product	Versions
linux	linux_kernel	5.11 — 5.12.10
linux	linux_kernel	All

References

Advisories & Patches

https://git.kernel.org/stable/c/1f64f5e903b9d1d157875721e02adadc9d6f0a5d https://git.kernel.org/stable/c/447c19f3b5074409c794b350b10306e1da1ef4ba https://git.kernel.org/stable/c/1f64f5e903b9d1d157875721e02adadc9d6f0a5d https://git.kernel.org/stable/c/447c19f3b5074409c794b350b10306e1da1ef4ba

Frequently Asked Questions

What is CVE-2021-47123? +

In the Linux kernel, the following vulnerability has been resolved: io_uring: fix ltout double free on completion race Always remove linked timeout on io_link_timeout_fn() from the master request link list, otherwise we may get use-after-free when first io_link_timeout_fn() puts linked timeout in the fail path, and then will be found and put on master's free. It has a CVSS v3.1 base score of 7.8 (HIGH).

How severe is CVE-2021-47123? +

CVE-2021-47123 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-2021-47123? +

CVE-2021-47123 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-2021-47123? +

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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CVE-2021-47123