CVE-2018-1087

Related Vulnerabilities: CVE-2018-1087  

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, 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.

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, 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.

Find out more about CVE-2018-1087 from the MITRE CVE dictionary dictionary and NIST NVD.

Statement

This issue does not affect the versions of Linux kernel as shipped with Red Hat Enterprise Linux 5, 6, and Red Hat Enterprise MRG 2.

This issue affects the version of the kernel package as shipped with Red Hat Enterprise Linux 7. Future kernel updates for Red Hat Enterprise Linux 7 may address this issue.

CVSS v3 metrics

CVSS3 Base Score 8
CVSS3 Base Metrics CVSS:3.0/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack Vector Adjacent Network
Attack Complexity Low
Privileges Required Low
User Interaction None
Scope Unchanged
Confidentiality High
Integrity Impact High
Availability Impact High

Red Hat Security Errata

Platform Errata Release Date
Red Hat Virtualization 4 Management Agent for RHEL 7 Hosts (redhat-virtualization-host) RHSA-2018:1710 2018-05-23
Red Hat Virtualization 4 Management Agent for RHEL 7 Hosts (rhev-hypervisor7) RHSA-2018:1711 2018-05-23
Red Hat Enterprise Linux for Real Time for NFV (v. 7) (kernel-rt) RHSA-2018:1355 2018-05-08
Red Hat Enterprise Linux Extended Update Support 7.4 (kernel) RHSA-2018:1345 2018-05-08
Red Hat Enterprise Linux Server TUS (v. 7.2) (kernel) RHSA-2018:1347 2018-05-08
Red Hat Enterprise Linux Server Update Services for SAP Solutions 7.2 (kernel) RHSA-2018:1347 2018-05-08
Red Hat Enterprise Linux Extended Update Support 7.3 (kernel) RHSA-2018:1348 2018-05-08
RHEV Hypervisor for RHEL-6 (rhev-hypervisor7) RHSA-2018:1711 2018-05-23
Red Hat Virtualization 4 Management Agent for RHEL 7 Hosts RHSA-2018:1524 2018-05-15
Red Hat Enterprise Linux 7 (kernel) RHSA-2018:1318 2018-05-08
Red Hat Enterprise Linux Advanced Update Support 7.2 (kernel) RHSA-2018:1347 2018-05-08

Affected Packages State

Platform Package State
Red Hat Enterprise MRG 2 kernel-rt Not affected
Red Hat Enterprise Linux 7 kernel-alt Not affected
Red Hat Enterprise Linux 6 kernel Not affected
Red Hat Enterprise Linux 5 kernel Not affected
RHEV Manager 3 rhev-hypervisor-ng Affected
RHEV Manager 3 rhev-hypervisor Affected

Acknowledgements

Red Hat would like to thank Andy Lutomirski for reporting this issue.

External References