CyberSecBulletin
CVE-2021-38647Exploited in the wildNVD status: Analyzed

Microsoft Open Management Infrastructure (OMI) Remote Code Execution

CVE-2021-38647 is a critical-severity vulnerability in Azure Automation State Configuration, DSC Extension from Microsoft, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists version DSC Agent versions: 2.71.1.25, 2.70.0.30, 3.0.0.3 as the first without the flaw, so updating Azure Automation State Configuration, DSC Extension to that release or later removes the exposure. CISA added it to the Known Exploited Vulnerabilities catalogue on November 3, 2021, which means attacks have been observed in the wild, including in ransomware campaigns.

Patch now

Attackers are already exploiting this vulnerability, according to CISA.

What to do

  1. Update Azure Automation State Configuration, DSC Extension to DSC Agent versions: 2.71.1.25, 2.70.0.30, 3.0.0.3 or a later version.
  2. Update Azure Automation Update Management to OMS Agent for Linux GA v1.13.40-0 or a later version.
  3. Update Azure Diagnostics (LAD) to LAD v4.0.13 and LAD v3.0.135 or a later version.
  4. CISA's required action: Apply updates per vendor instructions.
  5. Read the advisory on msrc.microsoft.com for workarounds and exact fixed builds.
  6. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
MicrosoftAzure Automation State Configuration, DSC Extension2.0.0 up to, but not including, DSC Agent versions: 2.71.1.25, 2.70.0.30, 3.0.0.3DSC Agent versions: 2.71.1.25, 2.70.0.30, 3.0.0.3
MicrosoftAzure Automation Update Management1.0.0 up to, but not including, OMS Agent for Linux GA v1.13.40-0OMS Agent for Linux GA v1.13.40-0
MicrosoftAzure Diagnostics (LAD)3.0.0 up to, but not including, LAD v4.0.13 and LAD v3.0.135LAD v4.0.13 and LAD v3.0.135
MicrosoftAzure Security Center1.0.0 up to, but not including, OMS Agent for Linux GA v1.13.40-0OMS Agent for Linux GA v1.13.40-0
MicrosoftAzure Sentinel1.0.0 up to, but not including, OMS Agent for Linux GA v1.13.40-0OMS Agent for Linux GA v1.13.40-0
MicrosoftAzure Stack Hub1.0.0 up to, but not including, Monitor, Update and Config Mgmnt 1.14.01Monitor, Update and Config Mgmnt 1.14.01
MicrosoftContainer Monitoring Solution1.0.0 up to, but not including, publicationpublication
MicrosoftLog Analytics Agent1.0.0 up to, but not including, OMS Agent for Linux GA v1.13.40-0OMS Agent for Linux GA v1.13.40-0
MicrosoftOpen Management Infrastructure16.0 up to, but not including, OMI Version 1.6.8-1OMI Version 1.6.8-1
MicrosoftSystem Center Operations Manager (SCOM)1.0.0 up to, but not including, OMI version: 1.6.8-1OMI version: 1.6.8-1
MicrosoftAzure Automation State ConfigurationNot specified in the recordNot stated
MicrosoftSystem Center Operations ManagerNot specified in the recordNot stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.19.8CriticalCNA (microsoft.com)
CVSS 3.19.8CriticalNVD
CVSS 2.07.5HighNVD

Official description

Open Management Infrastructure (OMI) Remote Code Execution Vulnerability

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

Timeline

  1. CVE record published.
  2. Added to CISA's Known Exploited Vulnerabilities catalogue.
  3. Deadline for US federal agencies to remediate, set by CISA.
  4. CISA published its SSVC assessment (exploitation: active, automatable: yes, technical impact: total).
  5. Record last changed materially (score, affected products, status or references).

References

Third-party and government advisories

Technical write-ups (may include proof of concept)

Other vulnerabilities in Azure Automation State Configuration, DSC Extension

All Azure Automation State Configuration, DSC Extension vulnerabilities

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