#VU11518 NULL pointer dereference in Linux kernel - CVE-2018-1092

Vulnerability identifier: #VU11518

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-2018-1092

CWE-ID: CWE-476

Exploitation vector: Local

Exploit availability: No

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

Vendor: Linux Foundation

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

The weakness exists due to improper processing of a customized ext4 image when using the ext4_iget function, as defined in the fs/ext4/inode.c source code file. A local attacker can mount a customized ext4 image, trigger NULL pointer dereference and an Out-of-Process Space (OOPS) kernel memory error and cause the service to crash.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Linux kernel: 4.0.1 - 4.0.6, 4.1 - 4.15.15, 4.2 - 4.2.6, 4.3 - 4.3.6, 4.4.0 - 4.4.111, 4.5 - 4.5.4, 4.6 rc1 - 4.6.3, 4.7 - 4.7.9, 4.8 - 4.8.11, 4.9 - 4.9.76

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External links
https://bugzilla.kernel.org/show_bug.cgi?id=199179

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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.