CVE-2019-10168
📋 TL;DR
This vulnerability in libvirt allows read-only clients to execute arbitrary programs with libvirtd privileges by specifying a crafted path in the 'emulator' argument of certain APIs. It affects libvirt versions 4.x.x before 4.10.1 and 5.x.x before 5.4.1. Systems using libvirt for virtualization management are at risk.
💻 Affected Systems
- libvirt
📦 What is this software?
Libvirt by Redhat
Libvirt by Redhat
⚠️ Risk & Real-World Impact
Worst Case
An attacker with read-only access to libvirt could execute arbitrary code with libvirtd privileges (typically root), leading to full system compromise, data theft, or lateral movement within the environment.
Likely Case
Privilege escalation from a low-privileged user or service account to root, enabling further system exploitation and control over virtual machines.
If Mitigated
If proper access controls limit libvirt API access to trusted users only, impact is reduced to authorized users misusing privileges.
🎯 Exploit Status
Exploitation requires read-only access to libvirt API. Public proof-of-concept exists, making weaponization likely.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: libvirt 4.10.1, 5.4.1, or later
Vendor Advisory: https://access.redhat.com/libvirt-privesc-vulnerabilities
Restart Required: Yes
Instructions:
1. Update libvirt packages to version 4.10.1+ or 5.4.1+ using your distribution's package manager. 2. Restart libvirtd service. 3. Verify the update with version check.
🔧 Temporary Workarounds
Restrict libvirt API access
linuxLimit access to libvirt API (e.g., via UNIX socket permissions or network firewall) to trusted users only.
chmod 750 /var/run/libvirt/libvirt-sock
chown root:libvirt /var/run/libvirt/libvirt-sock
🧯 If You Can't Patch
- Restrict libvirt API access to minimal trusted users via UNIX socket permissions or network ACLs.
- Monitor libvirtd logs for unusual emulator path executions and audit user access to libvirt.
🔍 How to Verify
Check if Vulnerable:
Check libvirt version with 'libvirtd --version' or package manager. If version is 4.x.x < 4.10.1 or 5.x.x < 5.4.1, system is vulnerable.Check Version:
libvirtd --versionVerify Fix Applied:
After update, confirm version is >= 4.10.1 or >= 5.4.1. Test with a read-only client attempting to specify an emulator path; it should fail or be restricted.📡 Detection & Monitoring
Log Indicators:
- Unusual emulator path executions in libvirtd logs (e.g., /var/log/libvirt/libvirtd.log)
- Failed authentication attempts or unexpected API calls from read-only clients.
Network Indicators:
- Unexpected network connections to libvirt ports (default 16509 TCP) from unauthorized sources.
SIEM Query:
source="libvirtd.log" AND "emulator" AND NOT "qemu-system"🔗 References
- https://access.redhat.com/libvirt-privesc-vulnerabilities
- https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-10168
- https://security.gentoo.org/glsa/202003-18
- https://access.redhat.com/libvirt-privesc-vulnerabilities
- https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-10168
- https://security.gentoo.org/glsa/202003-18
