CVE-2024-21334 Overview
CVE-2024-21334 is a remote code execution vulnerability affecting Microsoft Open Management Infrastructure (OMI). The flaw stems from a use-after-free condition [CWE-416] in the OMI service. Unauthenticated attackers can exploit it over the network without user interaction. Successful exploitation grants attackers the ability to execute arbitrary code in the context of the OMI service, which often runs with elevated privileges.
The vulnerability also impacts System Center Operations Manager (SCOM) 2019 and 2022, which embed OMI components. Given OMI's widespread deployment in Linux-based Azure management workloads and on-premises monitoring agents, the attack surface extends across hybrid environments.
Critical Impact
Unauthenticated network attackers can trigger a use-after-free in OMI to achieve remote code execution on affected SCOM and OMI deployments.
Affected Products
- Microsoft Open Management Infrastructure (OMI)
- Microsoft System Center Operations Manager 2019
- Microsoft System Center Operations Manager 2022
Discovery Timeline
- 2024-03-12 - CVE-2024-21334 published to NVD
- 2024-03-12 - Microsoft releases security update for OMI
- 2024-11-29 - Last updated in NVD database
Technical Details for CVE-2024-21334
Vulnerability Analysis
The vulnerability is a use-after-free condition [CWE-416] in the Open Management Infrastructure service. OMI is an open-source CIM/WBEM implementation used to manage Linux and UNIX systems. It is bundled into multiple Microsoft management products, including System Center Operations Manager.
When OMI processes specific requests over its HTTPS management endpoint, an object can be freed while a reference to it remains active. An attacker who reaches the listener can manipulate memory state to reuse the freed allocation. Controlling the contents of the dangling reference allows execution flow to be redirected.
The service typically listens on TCP port 5986 for HTTPS-based WBEM traffic. Internet-exposed OMI endpoints have historically been a high-value target, as seen in the prior OMIGOD vulnerability family.
Root Cause
The root cause is improper management of an object lifetime inside the OMI request-handling code. Memory is released while pointers to that allocation remain reachable. Subsequent operations dereference the stale pointer, producing memory corruption that an attacker can shape into code execution.
Attack Vector
The attack vector is network-based and requires no authentication or user interaction. An attacker sends crafted requests to an exposed OMI listener over the network. Because OMI runs with high privileges on managed hosts, successful exploitation yields full host compromise. Verified public proof-of-concept code is not currently listed, but the EPSS score places this vulnerability in the upper percentile for exploitation likelihood, warranting urgent remediation.
No verified public exploit code is available. Refer to the Microsoft Security Response Center advisory for technical context.
Detection Methods for CVE-2024-21334
Indicators of Compromise
- Unexpected inbound connections to TCP port 5986 or other OMI HTTPS listener ports from untrusted sources.
- Anomalous child processes spawned by omiserver or omiagent on Linux hosts, or by SCOM agent processes on Windows.
- New scheduled tasks, cron jobs, or persistence artifacts created shortly after inbound OMI traffic.
- Crash logs or service restarts of omiserver correlated with external network activity.
Detection Strategies
- Monitor SCOM management servers and Linux nodes running OMI for process lineage anomalies originating from OMI binaries.
- Inspect network telemetry for unauthenticated traffic to OMI management ports, particularly from outside management subnets.
- Correlate OMI service crashes with subsequent shell, scripting, or reconnaissance command execution on the same host.
Monitoring Recommendations
- Enable verbose logging on OMI listeners and forward logs to a centralized analytics platform for anomaly review.
- Audit SCOM management group inventories to identify every host with the OMI agent installed and its installed version.
- Alert on outbound connections initiated by OMI service accounts, which should not initiate external sessions during normal operation.
How to Mitigate CVE-2024-21334
Immediate Actions Required
- Apply the Microsoft security update for OMI and the corresponding SCOM 2019 and 2022 cumulative updates without delay.
- Inventory all Linux and Windows systems running OMI agents, including those deployed indirectly by SCOM, Azure Automation, or Log Analytics.
- Restrict OMI listener exposure to trusted management subnets using host firewalls and network access control lists.
- Rotate credentials and review for suspicious activity on hosts that exposed OMI endpoints to untrusted networks.
Patch Information
Microsoft has released updates addressing CVE-2024-21334. Administrators should consult the Microsoft CVE-2024-21334 advisory for fixed OMI versions and the corresponding SCOM update rollups. Update both the management server and all Linux monitoring agents, since the OMI package is distributed independently of the SCOM core installer.
Workarounds
- Block inbound traffic to OMI listener ports (commonly TCP 5985 and 5986) at perimeter and host firewalls when patching cannot be completed immediately.
- Disable the OMI HTTPS listener on systems that do not require remote management until updates are applied.
- Remove the OMI package from hosts that do not need agent-based monitoring.
# Verify installed OMI version on Linux hosts
/opt/omi/bin/omiserver --version
# Restrict OMI listener to management subnet using iptables
iptables -A INPUT -p tcp --dport 5986 -s 10.0.10.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 5986 -j DROP
# Stop and disable OMI where not required
systemctl stop omid
systemctl disable omid
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
