CVE-2021-47164: linux kernel Null Dereference — Fix

Description

In the Linux kernel, the following vulnerability has been resolved: net/mlx5e: Fix null deref accessing lag dev It could be the lag dev is null so stop processing the event. In bond_enslave() the active/backup slave being set before setting the upper dev so first event is without an upper dev. After setting the upper dev with bond_master_upper_dev_link() there is a second event and in that event we have an upper dev.

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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	Versions
linux	linux_kernel	5.8 — 5.10.42
linux	linux_kernel	5.11 — 5.12.9

References

Advisories & Patches

https://git.kernel.org/stable/c/2e4b0b95a489259f9d35a3db17023061f8f3d587 https://git.kernel.org/stable/c/83026d83186bc48bb41ee4872f339b83f31dfc55 https://git.kernel.org/stable/c/bdfd3593a8248eea6ecfcbf7b47b56b86515672d https://git.kernel.org/stable/c/2e4b0b95a489259f9d35a3db17023061f8f3d587 https://git.kernel.org/stable/c/83026d83186bc48bb41ee4872f339b83f31dfc55 https://git.kernel.org/stable/c/bdfd3593a8248eea6ecfcbf7b47b56b86515672d

Frequently Asked Questions

What is CVE-2021-47164? +

In the Linux kernel, the following vulnerability has been resolved: net/mlx5e: Fix null deref accessing lag dev It could be the lag dev is null so stop processing the event. In bond_enslave() the active/backup slave being set before setting the upper dev so first event is without an upper dev. After setting the upper dev with bond_master_upper_dev_link() there is a second event and in that event we have an upper dev. It has a CVSS v3.1 base score of 5.5 (MEDIUM).

How severe is CVE-2021-47164? +

CVE-2021-47164 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-2021-47164? +

CVE-2021-47164 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-2021-47164? +

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-2021-47164