#VU12853 Improper input validation in Linux kernel - CVE-2018-1120

Vulnerability identifier: #VU12853

Vulnerability risk: Low

CVSSv4.0: 5.4 [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:P/U:Clear]

CVE-ID: CVE-2018-1120

CWE-ID: CWE-20

Exploitation vector: Local

Exploit availability: Yes

Vulnerable software:
Linux kernel
Operating systems & Components / Operating system

Vendor: Linux Foundation

Description
The vulnerability allows a local user to cause DoS condition on the target system.

The weakness exists due to insufficient validation of user-supplied input. A local user can block any read() access to /proc/PID/cmdline by mmap()ing a FUSE file (Filesystem in Userspace) onto this process's command-line arguments, block pgrep, pidof, pkill, ps, and w, either forever (a denial of service), or for some controlled time (a synchronization tool for exploiting other vulnerabilities).

Mitigation
Update to version 4.11.

Vulnerable software versions

Linux kernel: 4.4 - 4.4.167, 4.10.0 - 4.10.17

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External links
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=7f7ccc2ccc2e70c6054685...
https://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.4.168

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