External risk intelligence

Microsoft OMI Privilege Escalation Vulnerability

CVE advisoryKnown Exploit

CVE-2021-38645

An elevation of privilege vulnerability exists in Microsoft's Open Management Infrastructure. Attackers with local access may escalate privileges, impacting affected systems and data. This poses a business risk due to potential unauthorized access and service disruption.

1Halo Surface Signal

Microsoft Azure Automation State Configuration

External exposure likelihood

Halo Surface Signal score for CVE-2021-38645

The vulnerability affects Open Management Infrastructure (OMI), which functions as a local system management agent. It is designed for internal administrative and diagnostic tasks on host systems, not for exposure to the public internet. Access requires local or authenticated system-level interaction, making public network reachability not a standard deployment pattern.

Horizon Alert

Summary of the vulnerability and why it matters

Microsoft's Open Management Infrastructure (OMI) is susceptible to an elevation of privilege vulnerability. This flaw allows an attacker with local access to escalate their privileges on the affected system. The potential impact includes unauthorized access to sensitive data and disruption of system operations.

  • Vulnerable: Open Management Infrastructure
  • Weakness: Elevation of privilege
  • Impact: Data access, system disruption

Attack Path

How an attacker could exploit the issue

This vulnerability allows an attacker to elevate privileges within an organization's systems. The attack requires local access to an affected system. Once access is gained, the attacker can execute commands to gain higher-level control. This could lead to unauthorized access to sensitive data or disruption of services.

  • Local system access required.
  • Attacker triggers action.
  • Attacker gains control.

Live Threat

Current exploitation, exposure, and threat context

This vulnerability impacts organizations using Microsoft's Open Management Infrastructure and related Azure services. Attackers with local access or specific credentials could exploit this to gain elevated privileges on affected systems. This elevation could lead to unauthorized access to sensitive data, disruption of services, and further compromise of the organization's environment, posing a significant business risk.

  • Attackers need local access.
  • Exploitation allows privilege escalation.
  • Business risk is significant.

Priority actions

Operational Fix

Recommended remediation, mitigation, and detection steps

This vulnerability impacts systems running Microsoft's Open Management Infrastructure (OMI), potentially allowing attackers with limited access to gain elevated privileges. Organizations should prioritize identifying and securing these affected assets to mitigate risk. The vulnerability has been noted on a government catalog of exploited vulnerabilities, underscoring the need for prompt action.

  • Find systems using OMI.
  • Isolate affected systems if possible.
  • Apply vendor updates and verify.
  • Monitor for suspicious activity.

Frequently asked questions

What is the Open Management Infrastructure Elevation of Privilege Vulnerability affecting Microsoft Azure services?

CVE-2021-38645 is an Elevation of Privilege Vulnerability in Microsoft's Open Management Infrastructure (OMI). This flaw allows a local attacker to escalate their privileges on an affected system, potentially leading to unauthorized data access or system disruption. It impacts various Microsoft products including Azure Automation State Configuration, Azure Automation Update Management, and Azure Sentinel.

What is the weakness class and trigger path for CVE-2021-38645?

The weakness class is an Elevation of Privilege. The trigger path involves an attacker gaining local system access to an affected machine running OMI. Once local access is achieved, the attacker can execute commands to escalate their privileges, thereby gaining higher-level control over the system without needing further authentication.

What is the scope of impact for this vulnerability and how can it be negated?

The scope of this vulnerability is local, meaning an attacker requires direct or authenticated local access to the affected system. Scope negation is not explicitly detailed, but the impact is contained to the system on which OMI is running and the attacker's ability to escalate privileges on that specific machine. The attack vector requires the attacker to already have a foothold on the system.

What is the relevance of the Halo Surface Signal for this vulnerability?

The Halo Surface Signal indicates this vulnerability is 'Very unlikely' to be exposed externally. OMI is designed for internal system management and diagnostic tasks, typically not exposed to the public internet. Its function as a local system agent means public network reachability is not a standard deployment pattern, limiting its direct external threat surface.

What practical steps should be taken to respond to this vulnerability?

Organizations should identify all systems running Microsoft Open Management Infrastructure (OMI) and related Azure services. If possible, isolate affected systems. The primary response is to apply vendor-provided updates to patch the vulnerability. Continuous monitoring for any suspicious activity on these systems is also recommended after patching.

References