NULL pointer dereference in Linux kernel selinux ss

1) NULL pointer dereference

EUVDB-ID: #VU90585

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-2021-47218

CWE-ID: CWE-476 - NULL Pointer Dereference

Exploit availability: No

Description

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

The vulnerability exists due to NULL pointer dereference within the hashtab_compute_size() function in security/selinux/ss/hashtab.c. A local user can perform a denial of service (DoS) attack.

Mitigation

Install update from vendor's website.

Vulnerable software versions

Linux kernel: All versions

CPE2.3

• cpe:2.3:o:linux_foundation:linux_kernel:*:*:*:*:*:*:*:*

External links

https://git.kernel.org/stable/c/b17dd53cac769dd13031b0ca34f90cc65e523fab
https://git.kernel.org/stable/c/83c8ab8503adf56bf68dafc7a382f4946c87da79
https://git.kernel.org/stable/c/dc27f3c5d10c58069672215787a96b4fae01818b

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.