Security restrictions bypass in Linux Kernel

1) Security restrictions bypass

EUVDB-ID: #VU16060

Risk: Low

CVSSv3.1: 4.6 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L/E:U/RL:O/RC:C]

CVE-ID: CVE-2018-16862

CWE-ID: CWE-20 - Improper input validation

Exploit availability: No

Description

The vulnerability allows a local attacker to bypass security restrictions on the target system.

The vulnerability exists due to an error when the cleancache subsystem clears an inode after the final file truncation (removal). A local attacker can supply new file created with the same inode that may contain leftover pages from cleancache and bypass security restrictions to conduct further attacks.

Mitigation

Install update from vendor's website.

Vulnerable software versions

Linux kernel: 4.15.0 - 4.19.3

External links

http://bugzilla.redhat.com/show_bug.cgi?id=1649017
http://lore.kernel.org/patchwork/patch/1011367/

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.