CVE-2021-47186: linux kernel Null Dereference — Fix

Description

In the Linux kernel, the following vulnerability has been resolved: tipc: check for null after calling kmemdup kmemdup can return a null pointer so need to check for it, otherwise the null key will be dereferenced later in tipc_crypto_key_xmit as can be seen in the trace [1]. [1] https://syzkaller.appspot.com/bug?id=bca180abb29567b189efdbdb34cbf7ba851c2a58

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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	5.5 — 5.10.82
linux	linux_kernel	5.11 — 5.15.5
linux	linux_kernel	All

References

Advisories & Patches

https://git.kernel.org/stable/c/3e6db079751afd527bf3db32314ae938dc571916 https://git.kernel.org/stable/c/9404c4145542c23019a80ab1bb2ecf73cd057b10 https://git.kernel.org/stable/c/a7d91625863d4ffed63b993b5e6dc1298b6430c9 https://git.kernel.org/stable/c/3e6db079751afd527bf3db32314ae938dc571916 https://git.kernel.org/stable/c/9404c4145542c23019a80ab1bb2ecf73cd057b10 https://git.kernel.org/stable/c/a7d91625863d4ffed63b993b5e6dc1298b6430c9

Frequently Asked Questions

What is CVE-2021-47186? +

In the Linux kernel, the following vulnerability has been resolved: tipc: check for null after calling kmemdup kmemdup can return a null pointer so need to check for it, otherwise the null key will be dereferenced later in tipc_crypto_key_xmit as can be seen in the trace [1]. [1] https://syzkaller.appspot.com/bug?id=bca180abb29567b189efdbdb34cbf7ba851c2a58 It has a CVSS v3.1 base score of 5.5 (MEDIUM).

How severe is CVE-2021-47186? +

CVE-2021-47186 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-2021-47186? +

CVE-2021-47186 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-2021-47186? +

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-2021-47186