Security Bulletin: Vulnerabilities in Samba affect IBM Spectrum Scale SMB protocol access method (CVE-2016-2126, 2016-2125)

Summary

Samba vulnerabilities affect IBM Spectrum Scale SMB protocol access method which could allow:

- a remote authenticated attacker to gain elevated privileges on the system, caused by forwarding a Ticket Granting Ticket (TGT) to other service when using Kerberos authentication. An attacker could exploit this vulnerability to impersonate the authenticated user and gain elevated privileges on the system (2016-2125)

- a remote authenticated attacker to gain elevated privileges on the system, caused by the failure of handling the PAC checksum. By using a specially-crafted Kerberos ticket, an authenticated attacker could exploit this vulnerability to gain privileges or cause the winbindd process to crash (2016-2126)

Vulnerability Details

CVEID: CVE-2016-2126 DESCRIPTION: Samba could allow a remote authenticated attacker to gain elevated privileges on the system, caused by the failure of handling the PAC checksum. By using a specially-crafted Kerberos ticket, an authenticated attacker could exploit this vulnerability to gain privileges or cause the winbindd process to crash.
CVSS Base Score: 6.3
CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/119906 for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L)

CVEID: CVE-2016-2125 DESCRIPTION: Samba could allow a remote authenticated attacker to gain elevated privileges on the system, caused by forwarding a Ticket Granting Ticket (TGT) to other service when using Kerberos authentication. An attacker could exploit this vulnerability to impersonate the authenticated user and gain elevated privileges on the system.
CVSS Base Score: 8.8
CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/119968 for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H)

Affected Products and Versions

IBM Spectrum Scale V4.2.0.0 thru V4.2.2.1

IBM Spectrum Scale V4.1.1.0 thru V4.1.1.11

Remediation/Fixes

For IBM Spectrum Scale V4.2.0.0 thru V4.2.2.1, apply V4.2.2.2 available from FixCentral at
https://www-945.ibm.com/support/fixcentral/swg/selectFixes?parent=Software%20defined%20storage&product=ibm/StorageSoftware/IBM+Spectrum+Scale&release=4.2.2&platform=All&function=all

For IBM Spectrum Scale V4.1.1.0 thru V4.1.1.11, apply V4.1.1.12 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

Workarounds and Mitigations

None