#VU63323 Buffer overflow in Linux kernel - CVE-2021-4157

Vulnerability identifier: #VU63323

Vulnerability risk: High

CVSSv4.0: 6.1 [CVSS:4.0/AV:A/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2021-4157

CWE-ID: CWE-119

Exploitation vector: Local network

Exploit availability: No

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

Vendor: Linux Foundation

Description

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to a boundary error in the Linux kernel NFS subsystem. A remote attacker can create a specially crafted data and crash the system or escalate privileges on the system

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Linux kernel: before 5.13, 5.13

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External links
https://bugzilla.redhat.com/show_bug.cgi?id=2034342
https://lore.kernel.org/lkml/20210517140244.822185482@linuxfoundation.org/

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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 local network (LAN).

Is there known malware, which exploits this vulnerability?

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