Security Bulletin: A vulnerability in Apache Log4j affects some features of IBM® Db2® (CVE-2021-44832)

Summary

The Apache Log4j open source library used by IBM® Db2® is affected by a vulnerability that could allow a remote attacker to execute arbitrary code on the system. This library is used by the Db2 Federation feature. The fix for the vulnerability is to update the log4j library to version 2.17.1. Please see CVE-2021-4104 for bulletin relating to Log4j V1. Please see CVE-2021-45046, CVE-2021-45105 and CVE-2021-44228 for bulletins relating to Log4j V2.

Vulnerability Details

CVEID:CVE-2021-44832
**DESCRIPTION:**Apache Log4j could allow a remote attacker with permission to modify the logging configuration file to execute arbitrary code on the system. By constructing a malicious configuration using a JDBC Appender with a data source referencing a JNDI URI , an attacker could exploit this vulnerability to execute remote code.
CVSS Base score: 6.6
CVSS Temporal Score: See: https://exchange.xforce.ibmcloud.com/vulnerabilities/216189 for the current score.
CVSS Vector: (CVSS:3.0/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H)

Affected Products and Versions

Fix pack levels of IBM Db2 V11.5 for all editions on all platforms are affected only if the following features are configured:

Federation:

• DVM JDBC wrapper driver,
• NoSQL wrapper driver (for Hadoop),
• Blockchain wrapper driver (for Hyperledger Fabric, Linux 64-bit, x86-64 only)

IBM Db2 V9.7, V10.1, V10.5 and V11.1 are not affected by this issue. Please note that log4j v1.x was removed in a previous build, and customers are strongly recommended to apply those fixes if you are on an older version of Db2. See Security Bulletin for details.

To determine if Federation is enabled, issue the following:

db2 get dbm cfg | grep FEDERATED

If a value of NO is returned, you are not vulnerable.

You can determine if you are using one of the affected wrappers by performing:

To determine if the DVM JDBC wrapper is in use, issue the following statement:

db2 “select servername from syscat.serveroptions where option = ‘DRIVER_CLASS’ and setting = ‘com.rs.jdbc.dv.DvDriver’”

If a servername is returned, then you are using the DVM JDBC wrapper via the DvDriver class.

To determine if the NoSQL hadoop wrapper is in use, issue the following statement:

db2 “select * from syscat.servers where servertype = ‘HDFSPARQUET’”

If 1 or more rows are returned, then NoSQL hadoop wrapper is in use.

To determine if the NoSQL Blockchain wrapper is in use, issue the following statement:

db2 “select * from syscat.serveroptions where option=‘PEER_URL’”

If 1 or more rows are returned, then NoSQL Blockchain wrapper is in use.

Remediation/Fixes

Customers running any vulnerable fixpack level of an affected Program, V11.5, 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 the V11.5.6 and V11.5.7 release. They can be applied to any affected fixpack level of the appropriate release to remediate this vulnerability.

AIX 64-bit
Linux 32-bit, x86-32
Linux 64-bit, x86-64
Linux 64-bit, POWER™ little endian
Linux 64-bit, System z®, System z9® or zSeries®
Windows 32-bit, x86
Windows 64-bit, x86

V11.5| 11.5.8| IT39584|

<https://www.ibm.com/support/pages/node/6830623&gt;

Workarounds and Mitigations

On a Unix-type system, if you are not using Federation wrappers, you can remove log4j jar files.