Description
A flaw was found in the way Linux kernel KVM hypervisor before 4.18 emulated instructions such as sgdt/sidt/fxsave/fxrstor. It did not check current privilege(CPL) level while emulating unprivileged instructions. An unprivileged guest user/process could use this flaw to potentially escalate privileges inside guest.
CVSS breakdown
CVSS 3.0
Attack Vector
Local
Attack Complexity
High
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High
Affected products
- Linux / Kernel4.18 – 4.18
References
- MAILING_LISThttps://lists.debian.org/debian-lts-announce/2018/07/msg00015.html
- MISChttps://bugzilla.redhat.com/show_bug.cgi?id=CVE-2018-10853
- VENDOR_ADVISORYhttps://usn.ubuntu.com/3777-1/
- MAILING_LISThttps://lists.debian.org/debian-lts-announce/2018/07/msg00016.html
- MISChttps://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=129a72a0d3c8e139a04512325384fe5ac119e74
- MAILING_LISThttps://lists.debian.org/debian-lts-announce/2018/07/msg00020.html
- VENDOR_ADVISORYhttps://usn.ubuntu.com/3777-2/
- MISChttps://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=3c9fa24ca7c9c47605672916491f79e8ccacb9e6
- MAILING_LISThttps://www.openwall.com/lists/oss-security/2018/09/02/1
- MAILING_LISThttp://lists.opensuse.org/opensuse-security-announce/2019-05/msg00043.html
- VENDOR_ADVISORYhttps://access.redhat.com/errata/RHSA-2019:2043
- VENDOR_ADVISORYhttps://access.redhat.com/errata/RHSA-2019:2029
- VENDOR_ADVISORYhttps://access.redhat.com/errata/RHSA-2020:0036
- VENDOR_ADVISORYhttps://access.redhat.com/errata/RHSA-2020:0103
- VENDOR_ADVISORYhttps://access.redhat.com/errata/RHSA-2020:0179