Denial of service in Linux Kernel

1) Use-after-free

EUVDB-ID: #VU24834

Risk: Low

CVSSv3.1: 5.5 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:H/E:P/RL:O/RC:C]

CVE-ID: CVE-2020-8428

CWE-ID: CWE-416 - Use After Free

Exploit availability: Yes

Description

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

The vulnerability exists due to a use-after-free error within the "may_create_in_sticky" in "fs/namei.c". A local user can cause a denial of service (OOPS) or possibly obtain sensitive information from kernel memory.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Linux kernel: 5.0 - 5.4.17

External links

http://www.openwall.com/lists/oss-security/2020/01/28/4
http://www.openwall.com/lists/oss-security/2020/02/02/1
http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=d0cb50185ae942b03c4327be322055d622dc79f6
http://github.com/torvalds/linux/commit/d0cb50185ae942b03c4327be322055d622dc79f6
http://www.openwall.com/lists/oss-security/2020/01/28/2

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. However, proof of concept for this vulnerability is available.