Apache log4j und Log4cxx: Mehrere Schwachstellen ermöglichen Manipulation von Dateien
WID-SEC-2026-2292 · first 13.07.2026 · updated 26.10.2026 · CVSS 5,8
What it is about
Apache log4j ist ein Framework zum Loggen von Anwendungsmeldungen in Java. Apache Log4cxx ist ein Logging-Framework für C++-Anwendungen, das flexible und konfigurierbare Logging-Funktionen bereitstellt. Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Apache log4j und Apache Log4cxx ausnutzen, um Dateien zu manipulieren.
Under what conditions?
Over the network and without logging in. This is the most dangerous combination: attackers can scan reachable devices automatically.
What can happen in the worst case
An attacker could use the vulnerability to
- Dateien zu manipulieren
Am I affected?
Affected according to the BSI:
- HCL Domino Rest API
- IBM Tivoli Netcool/OMNIbus
- IBM Operational Decision Manager
- IBM SPSS Modeler
- IBM License Metric Tool
- IBM Tivoli Network Manager
- IBM DB2
- IBM Business Automation Workflow
- Apache log4j <2.25.5
- Apache log4j <2.26.1
- Apache Log4cxx <1.7.0
- IBM App Connect Enterprise
and 2 more
The installed version is usually shown under “Help → About” or in the device’s admin interface.
What helps?
Update to at least:
- Apache log4j 2.25.5
- Apache log4j 2.26.1
- Apache Log4cxx 1.7.0
- IBM QRadar SIEM 7.5.0 UP16
- IBM QRadar SIEM 7.6.0 FP 3
Is the vulnerability already being exploited?
None of the CVEs is in the CISA catalogue of exploited vulnerabilities. That does not mean there are no attacks, only that none are documented.
Information and sources
- Original BSI advisory (WID)
- Apache Security Advisory vom 2026-07-12 logging.apache.org
- Apache Security Advisory vom 2026-07-12 logging.apache.org
- IBM Security Bulletin 7280602 vom 2026-07-21 www.ibm.com
- HCL Security Bulletin vom 2026-07-30 support.hcl-software.com
- IBM Security Bulletin 7283607 vom 2026-08-13 www.ibm.com
- IBM Security Bulletin 7285726 vom 2026-08-31 www.ibm.com
- IBM Security Bulletin 7285930 vom 2026-09-01 www.ibm.com
- IBM Security Bulletin 7286012 vom 2026-09-02 www.ibm.com
- IBM Security Bulletin 7286196 vom 2026-09-03 www.ibm.com
- IBM Security Bulletin 7290888 vom 2026-10-07 www.ibm.com
- IBM Security Bulletin 7291681 vom 2026-10-08 www.ibm.com
- IBM Security Bulletin 7291607 vom 2026-10-08 www.ibm.com
- IBM Security Bulletin 7293833 vom 2026-10-23 www.ibm.com
CVE: CVE-2026-40023, CVE-2026-49844
Source: BSI warning and information service (CERT-Bund); CISA. The assessment of the conditions is my reading of the BSI text; the external pages are in their original language.