#VU12520 Improper check or handling of exceptional conditions in Linux kernel - CVE-2018-1087

Vulnerability identifier: #VU12520

Vulnerability risk: Low

CVSSv4.0: 6.3 [CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2018-1087

CWE-ID: CWE-703

Exploitation vector: Local network

Exploit availability: No

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

Vendor: Linux Foundation

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

The weakness exists in the Linux kernel KVM hypervisor due to improper handling of debug exceptions delivered after a stack switch operation via mov SS or pop SS instructions. During the stack switch operation, the exceptions are deferred. An adjacent attacker can cause the service to crash or gain root privileges.

Mitigation
Update to version 4.16-rc7.

Vulnerable software versions

Linux kernel: 4.16 rc - 4.16 rc6

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External links
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=32d43cd391bacb5f0814c2624399a5dad3501d09

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the local network (LAN).

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.