#VU69431 Improper Privilege Management in Linux kernel - CVE-2020-35513

Vulnerability identifier: #VU69431

Vulnerability risk: Low

CVSSv4.0: 4 [CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2020-35513

CWE-ID: CWE-269

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 attack.

The vulnerability exists due to improper privilege management in the Linux kernel NFS (network file system) functionality in the way user create and delete object using NFSv4.2 or newer if both simultaneously accessing the NFS by the other process that is not using new NFSv4.2. A local user can trigger the vulnerability to starve the resources and perform a denial of service attack.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Linux kernel: before 4.17, 4.17

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External links
https://bugzilla.redhat.com/show_bug.cgi?id=1911309
https://patchwork.kernel.org/project/linux-nfs/patch/20180403203916.GH20297@fieldses.org/

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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.