Security Bulletin
Summary
IBM® Db2® is affected by a vulnerability in log4j-core.
Vulnerability Details
CVEID: CVE-2026-34479
DESCRIPTION: The Log4j1XmlLayout from the Apache Log4j 1-to-Log4j 2 bridge fails to escape characters forbidden by the XML 1.0 standard, producing malformed XML output. Conforming XML parsers are required to reject documents containing such characters with a fatal error, which may cause downstream log processing systems to drop or fail to index affected records.
Two groups of users are affected:
* Those using Log4j1XmlLayout directly in a Log4j Core 2 configuration file.
* Those using the Log4j 1 configuration compatibility layer with org.apache.log4j.xml.XMLLayout specified as the layout class.
Users are advised to upgrade to Apache Log4j 1-to-Log4j 2 bridge version 2.25.4, which corrects this issue.
Note: The Apache Log4j 1-to-Log4j 2 bridge is deprecated and will not be present in Log4j 3. Users are encouraged to consult the Log4j 1 to Log4j 2 migration guide https://logging.apache.org/log4j/2.x/migrate-from-log4j1.html , and specifically the section on eliminating reliance on the bridge.
CWE: CWE-116: Improper Encoding or Escaping of Output
CVSS Source: NVD
CVSS Base score: 7.5
CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N)
Affected Products and Versions
| Affected Product(s) | Version(s) | Applicable Editions |
| IBM® Db2® |
11.5.0 - 11.5.9 |
Server |
| IBM® Db2® |
12.1.0 - 12.1.4 |
Server |
All platforms are affected.
Remediation/Fixes
Customers running any vulnerable modpack level of an affected Program,V11.5, and V12.1, 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 level for each impacted release: V11.5.9, and V12.1.4. They can be applied to any affected level of the appropriate release to remediate this vulnerability.
| Release | Fixed in mod pack | APAR | Download URL |
|
V11.5 |
TBD |
Special Build #84653 or later for V11.5.9 available at this link: | |
|
V12.1
|
12.1.5
|
| Special Build #86230 or later for V12.1.4 available at this link: https://www.ibm.com/support/pages/node/7267513 |
IBM does not disclose key Db2 functionality nor replication steps for a vulnerability to avoid providing too much information to any potential malicious attacker. IBM does not want to enable a malicious attacker with sufficient knowledge to craft an exploit of the vulnerability.
Workarounds and Mitigations
None
Get Notified about Future Security Bulletins
References
Acknowledgement
Change History
10 Jul 2026: 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.
Disclaimer
According to the Forum of Incident Response and Security Teams (FIRST), the Common Vulnerability Scoring System (CVSS) is an "industry open standard designed to convey vulnerability severity and help to determine urgency and priority of response." IBM PROVIDES THE CVSS SCORES ""AS IS"" WITHOUT WARRANTY OF ANY KIND, INCLUDING THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. CUSTOMERS ARE RESPONSIBLE FOR ASSESSING THE IMPACT OF ANY ACTUAL OR POTENTIAL SECURITY VULNERABILITY. In addition to other efforts to address potential vulnerabilities, IBM periodically updates the record of components contained in our product offerings. As part of that effort, if IBM identifies previously unidentified packages in a product/service inventory, we address relevant vulnerabilities regardless of CVE date. Inclusion of an older CVEID does not demonstrate that the referenced product has been used by IBM since that date, nor that IBM was aware of a vulnerability as of that date. We are making clients aware of relevant vulnerabilities as we become aware of them. "Affected Products and Versions" referenced in IBM Security Bulletins are intended to be only products and versions that are supported by IBM and have not passed their end-of-support or warranty date. Thus, failure to reference unsupported or extended-support products and versions in this Security Bulletin does not constitute a determination by IBM that they are unaffected by the vulnerability. Reference to one or more unsupported versions in this Security Bulletin shall not create an obligation for IBM to provide fixes for any unsupported or extended-support products or versions.
Document Location
Worldwide
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Document Information
Modified date:
10 July 2026
Initial Publish date:
10 July 2026
UID
ibm17279458