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Security Bulletin: A vulnerability has been identified in IBM Spectrum Scale where mmfsd daemon can be prevented from servicing requests (CVE-2020-4925)

Security Bulletin


A security vulnerability has been identified in all levels of IBM Spectrum Scale where mmfsd daemon can be prevented from servicing requests. A fix for this vulnerability is available

Vulnerability Details

CVEID:   CVE-2020-4925
DESCRIPTION:   A security vulnerability in the Spectrum Scale allows a non-root user to overflow the mmfsd daemon with requests and preventing the daemon to service other requests.
CVSS Base score: 6.2
CVSS Temporal Score: See: for the current score.
CVSS Vector: (CVSS:3.0/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)

Affected Products and Versions

Affected Product(s)Version(s)
IBM Spectrum ScaleALL


For IBM Spectrum Scale levels lower than V5.1.1, apply V5.1.1 or later available (including 5.1.2 or later) from FixCentral at:

In addition to applying the recommended code level, ensure that the sdrNotifyAuthEnabled configuration variable is set to ‘yes’, which requires a cluster minimum release level of 5.1.1 or later.

See <<mmchconfig command>> for more details -


Note : Systems running supported version should be upgraded to the current release containing the security fixes.




Workarounds and Mitigations


Get Notified about Future Security Bulletins




Change History

11 Feb 2022: 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.


Review the IBM security bulletin disclaimer and definitions regarding your responsibilities for assessing potential impact of security vulnerabilities to your environment.

Document Location


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Document Information

Modified date:
03 March 2022