Security Bulletin: Under specific circumstances IBM® Db2® installation creates users with a weak password hashing algorithm (CVE-2017-1571).

Summary

When installed in Silent mode Db2 creates users with a weak password hashing algorithm, which results in only the first 8 characters of the supplied password being used, and remaining characters being ignored. This does not happen if existing users are used during installation; it only happens when Db2 creates the user during installation. The users created during installation are: instance owner, fenced user, and Db2 administration server (DAS) user.

This does not happen when Db2 installation is done in UI mode.

Vulnerability Details

CVEID: CVE-2017-1571 DESCRIPTION: IBM DB2 for Linux, UNIX and Windows (includes DB2 Connect Server) uses weaker than expected cryptographic algorithms that could allow an attacker to decrypt highly sensitive information.
CVSS Base Score: 5.1
CVSS Temporal Score: See https://exchange.xforce.ibmcloud.com/vulnerabilities/131853 for the current score
CVSS Environmental Score*: Undefined
CVSS Vector: (CVSS:3.0/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N)

Affected Products and Versions

All fix pack levels of IBM Db2 V9.7, V10.1, V10.5, and V11.1 editions on all platforms except Windows are affected.

Remediation/Fixes

The recommended solution is to apply the appropriate fix for this vulnerability and change passwords for the affected users.

FIX:
The fix for DB2 V11.1 is in V11.1.3 FP3, available for download from Fix Central.

Customers running any vulnerable fixpack level of an affected Program, V9.7, V10.1, and V10.5, can download the special build containing the interim fix for this issue from Fix Central. These special builds are available based on the most recent fixpack level for each impacted release: DB2 V9.7 FP11, V10.1 FP6, and V10.5 FP9. They can be applied to any affected fixpack level of the appropriate release to remediate this vulnerability.

AIX 64-bit
HP-UX 64-bit
Linux 32-bit, x86-32
Linux 64-bit, x86-64
Linux 64-bit, POWER™ big endian
Linux 64-bit, System z®, System z9® or zSeries®
Solaris 64-bit, SPARC
Solaris 64-bit, x86-64

V10.1 | TBD | IT22413 | Special Build for V10.1 FP6:

AIX 64-bit
HP-UX 64-bit
Linux 32-bit, x86-32
Linux 64-bit, x86-64
Linux 64-bit, POWER™ big endian
Linux 64-bit, System z®, System z9® or zSeries®
Solaris 64-bit, SPARC
Solaris 64-bit, x86-64

V10.5 | FP10 | IT22414 | <https://www-01.ibm.com/support/docview.wss?uid=swg24045012&gt;
V11.1.3 | FP3 | IT22415 | <https://www-01.ibm.com/support/docview.wss?uid=swg24044630&gt;

Workarounds and Mitigations

If installing Db2 in Silent mode, pre-create the users before the installation. This behaviour only occurs when Db2 creates the users during installation. Alternatively, perform the Db2 installation in UI mode.

If Db2 is already installed, you should change your password for the affected users (instance owner, fenced user, and Db2 administration server (DAS) user), which will use a stronger password hashing algorithm. Apply the special build if you will be performing Silent mode installation of Db2 without existing users.