#VU63914 Resource exhaustion in Linux kernel - CVE-2021-3759

Vulnerability identifier: #VU63914

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-2021-3759

CWE-ID: CWE-400

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 in the Linux kernel’s ipc functionality of the memcg subsystem when user calls the semget function multiple times, creating semaphores. A local user can trigger resource exhaustion and perform a denial of service (DoS) attack.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Linux kernel: before 5.15, 5.15

---

External links
http://access.redhat.com/errata/RHSA-2022:4814
http://bugzilla.redhat.com/show_bug.cgi?id=1999675

---

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.