#VU10921 Memory corruption in Linux kernel - CVE-2017-18221

Vulnerability identifier: #VU10921

Vulnerability risk: Low

CVSSv4.0: 4.3 [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:U/U:Clear]

CVE-ID: CVE-2017-18221

CWE-ID: CWE-119

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 in the __munlock_pagevec function due to boundary error when handling malicious input. A local attacker can execute specially crafted mlockall and munlockall system calls that submit malicious input, corrupt NR_MLOCK accounting and cause the system to crash.

Mitigation
Update to version 4.11.4.

Vulnerable software versions

Linux kernel: 4.10.0 - 4.11.3

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External links
https://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.11.4

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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.