CVE-2021-46905

MEDIUM
Published Feb 26, 2024 Modified Nov 21, 2024 CWE-476

Description

In the Linux kernel, the following vulnerability has been resolved: net: hso: fix NULL-deref on disconnect regression Commit 8a12f8836145 ("net: hso: fix null-ptr-deref during tty device unregistration") fixed the racy minor allocation reported by syzbot, but introduced an unconditional NULL-pointer dereference on every disconnect instead. Specifically, the serial device table must no longer be accessed after the minor has been released by hso_serial_tty_unregister().

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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

Weakness Type (CWE)

CWE-476 CWE-476

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
linux linux_kernel

References

Advisories & Patches

https://git.kernel.org/stable/c/0c71d4c89559f72cec2592d078681a843bce570e https://git.kernel.org/stable/c/0f000005da31f6947f843ce6b3e3a960540c6e00 https://git.kernel.org/stable/c/24b699bea7553fc0b98dad9d864befb6005ac7f1 https://git.kernel.org/stable/c/2ad5692db72874f02b9ad551d26345437ea4f7f3 https://git.kernel.org/stable/c/41c44e1f3112d7265dae522c026399b2a42d19ef https://git.kernel.org/stable/c/5871761c5f0f20d6e98bf3b6bd7486d857589554 https://git.kernel.org/stable/c/5c17cfe155d21954b4c7e2a78fa771cebcd86725 https://git.kernel.org/stable/c/90642ee9eb581a13569b1c0bd57e85d962215273 https://git.kernel.org/stable/c/d7fad2ce15bdbbd0fec3ebe999fd7cab2267f53e https://git.kernel.org/stable/c/0c71d4c89559f72cec2592d078681a843bce570e https://git.kernel.org/stable/c/0f000005da31f6947f843ce6b3e3a960540c6e00 https://git.kernel.org/stable/c/24b699bea7553fc0b98dad9d864befb6005ac7f1 https://git.kernel.org/stable/c/2ad5692db72874f02b9ad551d26345437ea4f7f3 https://git.kernel.org/stable/c/41c44e1f3112d7265dae522c026399b2a42d19ef https://git.kernel.org/stable/c/5871761c5f0f20d6e98bf3b6bd7486d857589554 https://git.kernel.org/stable/c/5c17cfe155d21954b4c7e2a78fa771cebcd86725 https://git.kernel.org/stable/c/90642ee9eb581a13569b1c0bd57e85d962215273 https://git.kernel.org/stable/c/d7fad2ce15bdbbd0fec3ebe999fd7cab2267f53e

Frequently Asked Questions

What is CVE-2021-46905? +
In the Linux kernel, the following vulnerability has been resolved: net: hso: fix NULL-deref on disconnect regression Commit 8a12f8836145 ("net: hso: fix null-ptr-deref during tty device unregistration") fixed the racy minor allocation reported by syzbot, but introduced an unconditional NULL-pointer dereference on every disconnect instead. Specifically, the serial device table must no longer be accessed after the minor has been released by hso_serial_tty_unregister(). It has a CVSS v3.1 base score of 5.5 (MEDIUM).
How severe is CVE-2021-46905? +
CVE-2021-46905 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-2021-46905? +
CVE-2021-46905 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-2021-46905? +
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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