#VU63383 NULL pointer dereference in Linux kernel - CVE-2021-38208

Vulnerability identifier: #VU63383

Vulnerability risk: Low

CVSSv4.0: 4.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-38208

CWE-ID: CWE-476

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Linux kernel
Operating systems & Components / Operating system

Vendor: Linux Foundation

Description

The vulnerability allows a remote user to perform a denial of service (DoS) attack.

The vulnerability exists due to a NULL pointer dereference error in the net/nfc/llcp_sock.c component. A remote attacker can make getsockname call and perform a denial of service (DoS) attack.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Linux kernel: 5.12 - 5.12.4

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External links
https://github.com/torvalds/linux/commit/4ac06a1e013cf5fdd963317ffd3b968560f33bba
https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.12.10
https://www.openwall.com/lists/oss-security/2021/08/17/1
https://www.openwall.com/lists/oss-security/2021/08/17/2
https://bugzilla.redhat.com/show_bug.cgi?id=1992810
https://www.openwall.com/lists/oss-security/2021/08/24/2

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.