CVE-2019-7222: Infoleak
An information leakage issue was found in the way Linux kernel's KVM hypervisor handled page fault exception while emulating instructions like VMXON, VMCLEAR, VMPTRLD, VMWRITE with memory address as an operand. It occurs if the operand is an mmio address, as the returned exception object holds uninitialised stack memory contents.
A guest user/process could use this flaw to leak host's stack memory contents to a guest.
It affects only Intel processors and only when nested virtualization is enabled.
Upstream patch: --------------- -> https://git.kernel.org/linus/353c0956a618a07ba4bbe7ad00ff29fe70e8412a
Reference: ---------- -> https://www.openwall.com/lists/oss-security/2019/02/18/2
Other sources
An information leakage issue was found in the way Linux kernel's KVM hypervisor handled page fault exceptions while emulating instructions like VMXON, VMCLEAR, VMPTRLD, and VMWRITE with memory address as an operand. It occurs if the operand is a mmio address, as the returned exception object holds uninitialized stack memory contents. A guest user/process could use this flaw to leak host's stack memory contents to a guest.
The KVM implementation in the Linux kernel through 4.20.5 has an Information Leak.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
redhat/kernel-rtto a version that resolves this vulnerability.Fixed in 0:3.10.0-1062.rt56.1022.el7 - Upgrade
Upgrade
redhat/kernelto a version that resolves this vulnerability.Fixed in 0:3.10.0-1062.el7 - Upgrade
Upgrade
redhat/kernel-rtto a version that resolves this vulnerability.Fixed in 0:4.18.0-147.rt24.93.el8 - Upgrade
Upgrade
redhat/kernelto a version that resolves this vulnerability.Fixed in 0:4.18.0-147.el8 - Upgrade
Upgrade
debian/linuxto a version that resolves this vulnerability.Fixed in 5.10.223-1Fixed in 5.10.262-1Fixed in 6.1.176-1Fixed in 6.1.180-1Fixed in 6.12.94-1Fixed in 6.12.101-1Fixed in 7.1.8-1Fixed in 7.1.8-2 - Upgrade
Upgrade
Linux kernel KVMto a version that resolves this vulnerability.Fixed in 4.20.5 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Patch VMPTRLD, VMWRITE with memory address as an operand - Compensating control
If nested virtualization is enabled and the guest can trigger KVM emulation of VMX instructions (VMXON, VMCLEAR, VMPTRLD, VMWRITE), treat this as an information-leak condition and restrict/limit nested virtualization exposure for affected Intel deployments until the upstream fix is applied.
Event History
Parent advisories
This vulnerability appears in the following advisories.
Frequently Asked Questions
What is the severity of CVE-2019-7222?
CVE-2019-7222 has been classified as a medium severity vulnerability.
How do I fix CVE-2019-7222?
To mitigate CVE-2019-7222, update your kernel to the version specified in the remedy for your Linux distribution.
Which versions are affected by CVE-2019-7222?
CVE-2019-7222 affects various versions of the Linux kernel, specifically those up to 4.20.5.
Is my system vulnerable to CVE-2019-7222?
To determine if your system is vulnerable to CVE-2019-7222, check the Linux kernel version against the affected versions.
What types of systems are affected by CVE-2019-7222?
CVE-2019-7222 impacts the Linux kernel, impacting systems running various distributions like Red Hat, Fedora, Debian, and Ubuntu.