CVE-2018-1087: High severity Linux Linux kernel vulnerability
A flaw was found in the way the Linux kernel's KVM hypervisor handled exceptions delivered after a stack switch operation via Mov SS or Pop SS instructions. During the stack switch operation, processor does not deliver interrupts and exceptions, they are delivered once the first instruction after the stack switch is executed.
An unprivileged KVM guest user could use this flaw to crash the guest and/or potentially escalate their privileges in the guest.
Upstream patch: --------------- -> https://git.kernel.org/linus/32d43cd391bacb5f0814c2624399a5dad3501d09
Reference: ---------- -> http://www.openwall.com/lists/oss-security/2018/05/08/5
Other sources
kernel KVM before versions kernel 4.16, kernel 4.16-rc7, kernel 4.17-rc1, kernel 4.17-rc2 and kernel 4.17-rc3 is vulnerable to a flaw in the way the Linux kernel's KVM hypervisor handled exceptions delivered after a stack switch operation via Mov SS or Pop SS instructions. During the stack switch operation, the processor did not deliver interrupts and exceptions, rather they are delivered once the first instruction after the stack switch is executed. An unprivileged KVM guest user could use this flaw to crash the guest or, potentially, escalate their privileges in the guest.
— Launchpad
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
redhat/kernelto a version that resolves this vulnerability.Fixed in 4.16 - Upgrade
Upgrade
redhat/kernelto a version that resolves this vulnerability.Fixed in 4.17 - Upgrade
Upgrade
debian/linuxto a version that resolves this vulnerability.Fixed in 5.10.223-1Fixed in 5.10.257-1Fixed in 6.1.170-3Fixed in 6.1.174-1Fixed in 6.12.86-1Fixed in 6.12.94-1Fixed in 7.0.13-1 - Upgrade
Upgrade
Linux kernel KVMto a version that resolves this vulnerability.Fixed in 4.16-rc7 - Upgrade
Upgrade
Linux kernel KVMto a version that resolves this vulnerability.Fixed in 4.17-rc1 - Upgrade
Upgrade
Linux kernel KVMto a version that resolves this vulnerability.Fixed in 4.17-rc2 - Upgrade
Upgrade
Linux kernel KVMto a version that resolves this vulnerability.Fixed in 4.17-rc3 - Upgrade
Upgrade
Linux kernel KVMto a version that resolves this vulnerability.Patch 32d43cd391bacb5f0814c2624399a5dad3501d09
Event History
Frequently Asked Questions
What is the severity of CVE-2018-1087?
CVE-2018-1087 has a moderate severity rating as it can lead to information disclosure or potential denial of service.
How do I fix CVE-2018-1087?
To fix CVE-2018-1087, you need to update your Linux kernel to version 4.16 or later for affected distributions.
Which Linux distributions are affected by CVE-2018-1087?
CVE-2018-1087 affects various Linux distributions including Red Hat Enterprise Linux, Debian, and Ubuntu.
What versions of the Linux kernel are vulnerable to CVE-2018-1087?
The vulnerable versions include the Linux kernel prior to 4.16, as well as the 4.17-rc1 through 4.17-rc3 releases.
Is there a risk of exploitation for CVE-2018-1087?
Yes, there is a risk of exploitation for CVE-2018-1087, particularly in environments that utilize KVM hypervisors.