Vulnerability identifier: #VU93596

Vulnerability risk: Low

CVSSv3.1: 4.8 [AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-4440

CWE-ID: CWE-399

Exploitation vector: Local

Exploit availability: No

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

Vendor: Linux Foundation

Description

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

The vulnerability exists due to resource management error within the SYM_CODE_START() function in arch/x86/xen/xen-asm.S, within the native_patch() function in arch/x86/kernel/paravirt_patch.c, within the paravirt_patch_default() and native_steal_clock() functions in arch/x86/kernel/paravirt.c, within the main() function in arch/x86/kernel/asm-offsets_64.c, within the SYM_INNER_LABEL() and SYM_CODE_END() functions in arch/x86/entry/entry_64.S. A local user can perform a denial of service (DoS) attack.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Linux kernel:

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External links
http://git.kernel.org/stable/c/1424ab4bb386df9cc590c73afa55f13e9b00dea2

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Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

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