NULL pointer dereference in Linux kernel

1) NULL pointer dereference

EUVDB-ID: #VU18539

Risk: Low

CVSSv3.1: 4.8 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2018-7191

CWE-ID: CWE-476 - NULL Pointer Dereference

Exploit availability: No

Description

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

The vulnerability exists due to a NULL pointer dereference error when processing requests to ioctl(TUNSETIFF). A local user can cause a denial of service  via a malicious ioctl(TUNSETIFF) call with a dev name containing a / character.

Mitigation

Install update from vendor's website.

Vulnerable software versions

Linux kernel: 4.13.1 - 4.13.13

External links

http://bugs.launchpad.net/ubuntu/+source/linux/+bug/1743792
http://bugs.launchpad.net/ubuntu/+source/linux/+bug/1748846
http://cdn.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.13.14
http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=0ad646c81b2182f7fa67ec0c8c825e0ee165696d
http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=5c25f65fd1e42685f7ccd80e0621829c105785d9
http://github.com/torvalds/linux/commit/0ad646c81b2182f7fa67ec0c8c825e0ee165696d
http://github.com/torvalds/linux/commit/5c25f65fd1e42685f7ccd80e0621829c105785d9

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.