CVE-2021-47239

HIGH
Published May 21, 2024 Modified Dec 30, 2024 CWE-416

Description

In the Linux kernel, the following vulnerability has been resolved: net: usb: fix possible use-after-free in smsc75xx_bind The commit 46a8b29c6306 ("net: usb: fix memory leak in smsc75xx_bind") fails to clean up the work scheduled in smsc75xx_reset-> smsc75xx_set_multicast, which leads to use-after-free if the work is scheduled to start after the deallocation. In addition, this patch also removes a dangling pointer - dev->data[0]. This patch calls cancel_work_sync to cancel the scheduled work and set the dangling pointer to NULL.

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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

References

Advisories & Patches

https://git.kernel.org/stable/c/14616c372a7be01a2fb8c56c9d8debd232b9e43d https://git.kernel.org/stable/c/2fc8300c9cfa5167fcb5b1a2a07db6f53e82f59b https://git.kernel.org/stable/c/4252bf6c2b245f47011098113d405ffad6ad5d5b https://git.kernel.org/stable/c/56b786d86694e079d8aad9b314e015cd4ac02a3d https://git.kernel.org/stable/c/570a52cf3e01d19f7fd1a251dfc52b0cd86c13cb https://git.kernel.org/stable/c/64160d1741a3de5204d1a822e058e0b4cc526504 https://git.kernel.org/stable/c/7cc8b2e05fcea6edd022d26e82091d781af8fd9b https://git.kernel.org/stable/c/c4e3be2e7742863e454ce31faf8fd0109c00050b https://git.kernel.org/stable/c/14616c372a7be01a2fb8c56c9d8debd232b9e43d https://git.kernel.org/stable/c/2fc8300c9cfa5167fcb5b1a2a07db6f53e82f59b https://git.kernel.org/stable/c/4252bf6c2b245f47011098113d405ffad6ad5d5b https://git.kernel.org/stable/c/56b786d86694e079d8aad9b314e015cd4ac02a3d https://git.kernel.org/stable/c/570a52cf3e01d19f7fd1a251dfc52b0cd86c13cb https://git.kernel.org/stable/c/64160d1741a3de5204d1a822e058e0b4cc526504 https://git.kernel.org/stable/c/7cc8b2e05fcea6edd022d26e82091d781af8fd9b https://git.kernel.org/stable/c/c4e3be2e7742863e454ce31faf8fd0109c00050b

Frequently Asked Questions

What is CVE-2021-47239? +
In the Linux kernel, the following vulnerability has been resolved: net: usb: fix possible use-after-free in smsc75xx_bind The commit 46a8b29c6306 ("net: usb: fix memory leak in smsc75xx_bind") fails to clean up the work scheduled in smsc75xx_reset-> smsc75xx_set_multicast, which leads to use-after-free if the work is scheduled to start after the deallocation. In addition, this patch also removes a dangling pointer - dev->data[0]. This patch calls cancel_work_sync to cancel the scheduled work and set the dangling pointer to NULL. It has a CVSS v3.1 base score of 7.8 (HIGH).
How severe is CVE-2021-47239? +
CVE-2021-47239 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-2021-47239? +
CVE-2021-47239 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-2021-47239? +
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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