CVE-2019-14835
📋 TL;DR
This CVE describes a buffer overflow vulnerability in the Linux kernel's vhost functionality during live migration. A privileged guest user in a virtualized environment can exploit this flaw to escalate privileges on the host system. Systems running Linux kernel versions 2.6.34 through 5.2.x with virtualization enabled are affected.
💻 Affected Systems
- Linux Kernel
📦 What is this software?
Fedora by Fedoraproject
Fedora by Fedoraproject
Leap by Opensuse
Leap by Opensuse
Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →Linux Kernel by Linux
The Linux Kernel is the core component of the Linux operating system, serving as the critical interface between computer hardware and software processes. As the heart of millions of servers, cloud infrastructure, embedded systems, Android devices, and IoT deployments worldwide, the Linux Kernel mana...
Learn more about Linux Kernel →Manageone by Huawei
Manageone by Huawei
Manageone by Huawei
Manageone by Huawei
Manageone by Huawei
Solidfire by Netapp
Steelstore Cloud Integrated Storage by Netapp
View all CVEs affecting Steelstore Cloud Integrated Storage →
Ubuntu Linux by Canonical
Ubuntu Linux by Canonical
Ubuntu Linux by Canonical
Ubuntu Linux by Canonical
Ubuntu Linux by Canonical
⚠️ Risk & Real-World Impact
Worst Case
Privileged guest user gains root access on the host kernel, leading to complete host compromise and potential lateral movement to other virtual machines.
Likely Case
Privileged guest user escalates privileges on the host, potentially gaining control over other VMs and host resources.
If Mitigated
With proper access controls and minimal guest privileges, impact is limited to the specific vulnerable guest VM.
🎯 Exploit Status
Exploitation requires privileged guest access and specific migration conditions. Public exploit code exists in security advisories.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Linux kernel 5.3 and later
Vendor Advisory: https://www.kernel.org/
Restart Required: Yes
Instructions:
1. Update Linux kernel to version 5.3 or later. 2. Apply vendor-specific kernel patches if available. 3. Reboot the system to load the patched kernel.
🔧 Temporary Workarounds
Disable vhost during migration
linuxTemporarily disable vhost functionality when performing live migrations
echo 0 > /sys/module/vhost/parameters/max_queues
Restrict guest privileges
linuxLimit guest user privileges to prevent exploitation
chmod 750 /dev/vhost-net
setfacl -m u:libvirt-qemu:rw- /dev/vhost-net
🧯 If You Can't Patch
- Implement strict access controls for guest users and limit migration capabilities
- Monitor for unusual migration activities and privilege escalation attempts
🔍 How to Verify
Check if Vulnerable:
Check kernel version: uname -r and compare to affected range 2.6.34-5.2.xCheck Version:
uname -rVerify Fix Applied:
Verify kernel version is 5.3 or later: uname -r | grep -E '^5\.[3-9]|^[6-9]'📡 Detection & Monitoring
Log Indicators:
- Kernel panic messages
- vhost-related errors in dmesg
- Unusual migration activities in libvirt logs
Network Indicators:
- Unexpected migration traffic between hosts
- Suspicious guest-to-host communication patterns
SIEM Query:
source="kernel" AND ("vhost" OR "buffer overflow") AND severity>=high🔗 References
- http://lists.opensuse.org/opensuse-security-announce/2019-09/msg00064.html
- http://lists.opensuse.org/opensuse-security-announce/2019-09/msg00066.html
- http://packetstormsecurity.com/files/154572/Kernel-Live-Patch-Security-Notice-LSN-0056-1.html
- http://packetstormsecurity.com/files/154951/Kernel-Live-Patch-Security-Notice-LSN-0058-1.html
- http://packetstormsecurity.com/files/155212/Slackware-Security-Advisory-Slackware-14.2-kernel-Updates.html
- http://www.huawei.com/en/psirt/security-advisories/huawei-sa-20200115-01-qemu-en
- http://www.openwall.com/lists/oss-security/2019/09/24/1
- http://www.openwall.com/lists/oss-security/2019/10/03/1
- http://www.openwall.com/lists/oss-security/2019/10/09/3
- http://www.openwall.com/lists/oss-security/2019/10/09/7
- https://access.redhat.com/errata/RHBA-2019:2824
- https://access.redhat.com/errata/RHSA-2019:2827
- https://access.redhat.com/errata/RHSA-2019:2828
- https://access.redhat.com/errata/RHSA-2019:2829
- https://access.redhat.com/errata/RHSA-2019:2830
- https://access.redhat.com/errata/RHSA-2019:2854
- https://access.redhat.com/errata/RHSA-2019:2862
- https://access.redhat.com/errata/RHSA-2019:2863
- https://access.redhat.com/errata/RHSA-2019:2864
- https://access.redhat.com/errata/RHSA-2019:2865
- https://access.redhat.com/errata/RHSA-2019:2866
- https://access.redhat.com/errata/RHSA-2019:2867
- https://access.redhat.com/errata/RHSA-2019:2869
- https://access.redhat.com/errata/RHSA-2019:2889
- https://access.redhat.com/errata/RHSA-2019:2899
- https://access.redhat.com/errata/RHSA-2019:2900
- https://access.redhat.com/errata/RHSA-2019:2901
- https://access.redhat.com/errata/RHSA-2019:2924
- https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-14835
- https://lists.debian.org/debian-lts-announce/2019/09/msg00025.html
- https://lists.debian.org/debian-lts-announce/2019/10/msg00000.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/KQFY6JYFIQ2VFQ7QCSXPWTUL5ZDNCJL5/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/YW3QNMPENPFEGVTOFPSNOBL7JEIJS25P/
- https://seclists.org/bugtraq/2019/Nov/11
- https://seclists.org/bugtraq/2019/Sep/41
- https://security.netapp.com/advisory/ntap-20191031-0005/
- https://usn.ubuntu.com/4135-1/
- https://usn.ubuntu.com/4135-2/
- https://www.debian.org/security/2019/dsa-4531
- https://www.openwall.com/lists/oss-security/2019/09/17/1
- http://lists.opensuse.org/opensuse-security-announce/2019-09/msg00064.html
- http://lists.opensuse.org/opensuse-security-announce/2019-09/msg00066.html
- http://packetstormsecurity.com/files/154572/Kernel-Live-Patch-Security-Notice-LSN-0056-1.html
- http://packetstormsecurity.com/files/154951/Kernel-Live-Patch-Security-Notice-LSN-0058-1.html
- http://packetstormsecurity.com/files/155212/Slackware-Security-Advisory-Slackware-14.2-kernel-Updates.html
- http://www.huawei.com/en/psirt/security-advisories/huawei-sa-20200115-01-qemu-en
- http://www.openwall.com/lists/oss-security/2019/09/24/1
- http://www.openwall.com/lists/oss-security/2019/10/03/1
- http://www.openwall.com/lists/oss-security/2019/10/09/3
- http://www.openwall.com/lists/oss-security/2019/10/09/7
- https://access.redhat.com/errata/RHBA-2019:2824
- https://access.redhat.com/errata/RHSA-2019:2827
- https://access.redhat.com/errata/RHSA-2019:2828
- https://access.redhat.com/errata/RHSA-2019:2829
- https://access.redhat.com/errata/RHSA-2019:2830
- https://access.redhat.com/errata/RHSA-2019:2854
- https://access.redhat.com/errata/RHSA-2019:2862
- https://access.redhat.com/errata/RHSA-2019:2863
- https://access.redhat.com/errata/RHSA-2019:2864
- https://access.redhat.com/errata/RHSA-2019:2865
- https://access.redhat.com/errata/RHSA-2019:2866
- https://access.redhat.com/errata/RHSA-2019:2867
- https://access.redhat.com/errata/RHSA-2019:2869
- https://access.redhat.com/errata/RHSA-2019:2889
- https://access.redhat.com/errata/RHSA-2019:2899
- https://access.redhat.com/errata/RHSA-2019:2900
- https://access.redhat.com/errata/RHSA-2019:2901
- https://access.redhat.com/errata/RHSA-2019:2924
- https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-14835
- https://lists.debian.org/debian-lts-announce/2019/09/msg00025.html
- https://lists.debian.org/debian-lts-announce/2019/10/msg00000.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/KQFY6JYFIQ2VFQ7QCSXPWTUL5ZDNCJL5/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/YW3QNMPENPFEGVTOFPSNOBL7JEIJS25P/
- https://seclists.org/bugtraq/2019/Nov/11
- https://seclists.org/bugtraq/2019/Sep/41
- https://security.netapp.com/advisory/ntap-20191031-0005/
- https://usn.ubuntu.com/4135-1/
- https://usn.ubuntu.com/4135-2/
- https://www.debian.org/security/2019/dsa-4531
- https://www.openwall.com/lists/oss-security/2019/09/17/1
