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Powervm Hypervisor FirmwareOperating system · Ibm

CVE-2021-38923

CRITICAL · 9.1 CVSS v3.1 Published 2021-10-06
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
97/100
Remediation priority · Urgent
Remotely reachable Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
IBM PowerVM Hypervisor FW1010 could allow a privileged user to gain access to another VM due to assigning duplicate WWPNs. IBM X-Force ID: 210162.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · moderate confidence

IBM PowerVM Hypervisor FW1010 contains a vulnerability where duplicate World Wide Port Names (WWPNs) can be assigned to virtual machines. This configuration error allows a privileged user on one VM to potentially gain unauthorized access to another VM's storage resources by exploiting the duplicate WWPN assignment.

MitigationApply the IBM PowerVM Hypervisor firmware update to address the duplicate WWPN assignment vulnerability. Additionally, implement strict WWPN configuration management and validation procedures to prevent duplicate assignments.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Powervm Hypervisor FirmwareOperating system
Affected:= 1010

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
High
User interaction
None
Scope
Changed
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify the PowerVM Hypervisor firmware version
    Use the IBM HMC (Hardware Management Console) or IVM (Integrated Virtualization Manager) to view the hypervisor firmware version. From the HMC, go to Systems Management > Servers > select the server > Properties > Hypervisor Version. Or run 'lshwres -r proc --rsubtype all -m <managed_system>' via HMC CLI.
    Affected if The hypervisor firmware version is exactly 1010
  2. Confirm virtual machines have vHBA adapters configured
    Check if any LPARs (Logical Partitions) have Virtual SCSI Host Bus Adapters (vHBAs) assigned, which provide WWPN-based storage access. From HMC, go to LPAR Configuration > Virtual Adapters, or run 'lshwres -r virtualio --rsubtype vscsi --level lpar -m <managed_system>'.
    Affected if Any LPARs have vHBA adapters configured with WWPNs
  3. Export all WWPN assignments across the environment
    Collect the WWPNs assigned to all vHBAs. From HMC CLI, run 'lshwres -r virtualio --rsubtype vscsi --level lpar -m <managed_system>' and note the 'wwpns' field for each LPAR. Alternatively, use 'lsmap -all' from within each LPAR if you have access.
    Affected if You are able to retrieve a list of WWPN values from vHBA configurations
  4. Identify duplicate WWPN values
    Compare the collected WWPN values and look for duplicates. Use a spreadsheet, script, or 'sort | uniq -d' command to find WWPNs that appear more than once in the list.
    Affected if Two or more LPARs share the exact same WWPN value

You are affected if your system runs PowerVM Hypervisor Firmware version 1010, has vHBAs configured with WWPNs, and two or more virtual machines are assigned the same WWPN.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Apply the IBM PowerVM Hypervisor firmware update to address the duplicate WWPN assignment vulnerability. Additionally, implement strict WWPN configuration management and validation procedures to prevent duplicate assignments.

Recommended fix Moderate confidence

IBM PowerVM Hypervisor Firmware version higher than 1010 (contact IBM support for specific fixed release)

  1. Contact IBM Support or visit the IBM PowerVM support portal to obtain the firmware update for CVE-2021-38923
  2. Download the latest PowerVM Hypervisor Firmware that includes the fix for duplicate WWPN assignment vulnerability
  3. Schedule a maintenance window following IBM PowerVM firmware update procedures
  4. Update the PowerVM Hypervisor Firmware to the fixed release
  5. Verify the firmware update was applied successfully
  6. Confirm that WWPN assignments are unique across all Virtual I/O Servers and client partitions
Caveat Firmware updates may require system reboot; coordinate with业务 continuity plans

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Powervm Hypervisor Firmware Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing6.0 h
  • Review / QA4.0 h
22.0 hours of engineering $3,860
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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2021-38923 in production — separate from our analysis above.

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What this is

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What belongs here
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  • Version or environment caveats, and links to real fixes
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