#VU9693 Race condition in Linux kernel - CVE-2017-10661

Vulnerability identifier: #VU9693

Vulnerability risk: Low

CVSSv4.0: 7.1 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P/U:Clear]

CVE-ID: CVE-2017-10661

CWE-ID: CWE-362

Exploitation vector: Local

Exploit availability: Yes

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

Vendor: Linux Foundation

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

The weakness exists due to race condition in fs/timerfd.c in the Linux kernel. A local attacker can use simultaneous file-descriptor operations, leverage improper might_cancel queueing, trigger list corruption or use-after-free and cause the service to crash or execute arbitrary code with root privileges.

Mitigation
Update to version 4.10.15.

Vulnerable software versions

Linux kernel: 4.0.1 - 4.0.9, 4.1.1 - 4.10.14, 4.2.0 - 4.2.8, 4.3.1 - 4.3.6, 4.4.0 - 4.4.106, 4.5.0 - 4.5.7, 4.6.0 - 4.6.7, 4.7.0 - 4.7.10, 4.8.0 - 4.8.17, 4.9.1 - 4.9.70

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External links
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=1e38da300e1e395a15048b...

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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.