CVE-2021-38918Network attack vector

Peer-VM data disclosure via management operations

Published Jan 5, 2022 · Updated Sep 16, 2024

Information disclosure in IBM PowerVM Hypervisor FW860, FW940, FW950, and FW1010 allows attackers to access peer-VM data. An undisclosed sequence of HMC, Novalink, or PowerVC operations causes the hypervisor to fail to preserve isolation between peer virtual machines. The sequence must be issued through a management console, and the documented consequence is peer-VM data disclosure without alteration or service interruption.

CVSS severity8.6
High
EPSS probability1.21%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Information disclosure in IBM PowerVM Hypervisor FW860, FW940, FW950, and FW1010 allows attackers to access peer-VM data. An undisclosed sequence of HMC, Novalink, or PowerVC operations causes the hypervisor to fail to preserve isolation between peer virtual machines. The sequence must be issued through a management console, and the documented consequence is peer-VM data disclosure without alteration or service interruption.

The record

CVE
CVE-2021-38918
Published
Jan 5, 2022
Updated
Sep 16, 2024
Vendor
IBM
Product
PowerVM Hypervisor
Classifications
T1611
Attack vector
network
Privileges
Unavailable

Timeline

How it unfolded

  1. Jan 5, 2022CVE publishedPublication date reported by the CVE source.
  2. Sep 16, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=FW1010
  2. Affected versionversion=FW860
  3. Affected versionversion=FW940
  4. Affected versionversion=FW950

What conditions does exploitation require?

Attack vectornetwork
Required privilegesUnavailable in this record.

What is affected?

IBM · PowerVM Hypervisorversion=FW1010; version=FW860; version=FW940; version=FW950

Published CVSS scores

5.0NIST NVDAV:N/AC:L/Au:N/C:P/I:N/A:N
7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
8.6IBM CorporationCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1611Escape to Host

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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