#VU24438 Memory leak in Linux kernel - CVE-2019-19922

Vulnerability identifier: #VU24438

Vulnerability risk: Low

CVSSv4.0: 4.3 [CVSS:4.0/AV:L/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-2019-19922

CWE-ID: CWE-401

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 DoS attack on the target system.

The vulnerability exists due memory leak in "kernel/sched/fair.c" when "cpu.cfs_quota_us" is used (e.g., with Kubernetes). A local user can cause a denial of service against non-cpu-bound applications by generating a workload that triggers unwanted slice expiration.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Linux kernel: 5.3 - 5.3.8

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External links
https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.3.9
https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=de53fd7aedb100f03e5d2231cfce0e4993282425
https://github.com/kubernetes/kubernetes/issues/67577
https://github.com/torvalds/linux/commit/de53fd7aedb100f03e5d2231cfce0e4993282425
https://lists.debian.org/debian-lts-announce/2020/01/msg00013.html
https://relistan.com/the-kernel-may-be-slowing-down-your-app
https://usn.ubuntu.com/4226-1/

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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.