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Security Bulletin: This Power System update is being released to address CVE 2021-20505

Security Bulletin


POWER9: In response to a weakness in a set of PowerVM service procedures a new Power System firmware update is being released to address Common Vulnerabilities and Exposures issue number CVE 2021-20505.

Vulnerability Details

CVEID:   CVE-2021-20505
DESCRIPTION:   The PowerVM Logical Partition Mobility(LPM) encryption key exchange protocol can be compromised. If an attacker has the ability to capture encrypted LPM network traffic and is able to gain service access to the FSP they can use this information to perform a series of PowerVM service procedures to decrypt the captured migration traffic
CVSS Base score: 4.4
CVSS Temporal Score: See: for the current score.
CVSS Vector: (CVSS:3.0/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:N/A:N)

Affected Products and Versions

Affected Product(s)Version(s)
PowerVM Hypervisor
PowerVM HypervisorFW930
PowerVM HypervisorFW940
PowerVM HypervisorFW950


Customers with the products below should install FW930.40(VL930_134), FW940.30(VL940_071), FW950.00(VL950_045) or above to remediate this concern.
1) IBM Power System S922 (9009-22A, 9009-22G)

2) IBM Power System H922 (9223-22H, 9223-22S)

3) IBM Power System S914 (9009-41A, 9009-41G)

4) IBM Power System S924 (9009-42A, 9009-42G)

5) IBM Power System H924 (9223-42H, 9223-42S)

6) IBM Power System E950 (9040-MR9)

7) IBM Power System E980 (9080-M98, 9080-M9S)

Workarounds and Mitigations


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Change History

06 Apr 2021: Initial Publication

*The CVSS Environment Score is customer environment specific and will ultimately impact the Overall CVSS Score. Customers can evaluate the impact of this vulnerability in their environments by accessing the links in the Reference section of this Security Bulletin.


According to the Forum of Incident Response and Security Teams (FIRST), the Common Vulnerability Scoring System (CVSS) is an "industry open standard designed to convey vulnerability severity and help to determine urgency and priority of response." IBM PROVIDES THE CVSS SCORES ""AS IS"" WITHOUT WARRANTY OF ANY KIND, INCLUDING THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. CUSTOMERS ARE RESPONSIBLE FOR ASSESSING THE IMPACT OF ANY ACTUAL OR POTENTIAL SECURITY VULNERABILITY.

Document Location


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Document Information

Modified date:
28 July 2021