Security Bulletin: A vulnerability has been identified in IBM Spectrum Scale where the use of Local Read Only Cache (LROC) may result in directory corruption and undetected data corruption in regular files.

Summary

After cached data is moved from memory to the LROC device, any changes to that data should trigger invalidation of the data stored in LROC. Due to a problem with invalidation logic, it is possible for invalidation of this LROC data to be skipped. This could lead to stale or incorrect data to be recalled from LROC and data in memory to become corrupted, with potential for the data on disks to also become corrupted.

Vulnerability Details

CVEID: CVE-2018-1993 DESCRIPTION: IBM Spectrum Scale (GPFS) where the use of Local Read Only Cache (LROC) is enabled may caused read operation on a file to return data from a different file.
CVSS Base Score: 4
CVSS Temporal Score: See <https://exchange.xforce.ibmcloud.com/vulnerabilities/154440&gt; for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (CVSS:3.0/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N)

Affected Products and Versions

IBM Spectrum Scale V5.0.0.0 thru V5.0.2.0

IBM Spectrum Scale V4.2.0.0 thru V4.2.3.11

IBM Spectrum Scale V4.1.1.0 thru V4.1.1.21

Remediation/Fixes

For IBM Spectrum Scale V5.0.0.0 thru 5.0.2.0, apply V5.0.2.1 available from FixCentral at:
https://www-945.ibm.com/support/fixcentral/swg/selectFixes?parent=Software%20defined%20storage&product=ibm/StorageSoftware/IBM+Spectrum+Scale&release=5.0.2&platform=All&function=all

For IBM Spectrum Scale V4.2.0.0 thru V4.2.3.11, apply V4.2.3.12 available from FixCentral at:
https://www-945.ibm.com/support/fixcentral/swg/selectFixes?parent=Software%20defined%20storage&product=ibm/StorageSoftware/IBM+Spectrum+Scale&release=4.2.3&platform=All&function=all

For IBM Spectrum Scale V4.1.0.0 (GPFS) thru V4.1.1.21, apply V4.1.1.22 available from FixCentral at:
https://www-945.ibm.com/support/fixcentral/swg/selectFixes?parent=Software%2Bdefined%2Bstorage&product=ibm/StorageSoftware/IBM+Spectrum+Scale&release=4.1.1&platform=All&function=all

If you cannot apply the latest level of service, contact IBM Service for an efix:

- For IBM Spectrum Scale V5.0.0.0 thru V5.0.2.0, reference APAR IJ10565
- For IBM Spectrum Scale V4.2.0.0 thru V4.2.3.11, reference APAR IJ10573
- For IBM Spectrum Scale V4.1.1.0 thru V4.1.1.21, reference APAR IJ11409

To contact IBM Service, see http://www.ibm.com/planetwide/

Workarounds and Mitigations

Work-around : Although IBM recommends that you install a level of IBM Spectrum Scale code with a fix, you can avoid this vulnerability by not enabling Local Read Only (LROC) feature in IBM Spectrum Scale.