6.3
Medium
CVE-2026-40023 Apache Log4cxx's XMLLayout https://logging.apache.org/log4cxx/1.7.0/classlog4cxx_1_1xml_1_1XMLLayout.html , in versions…
Description
Apache Log4cxx's XMLLayout https://logging.apache.org/log4cxx/1.7.0/classlog4cxx_1_1xml_1_1XMLLayout.html , in versions before 1.7.0, fails to sanitize characters forbidden by the XML 1.0 specification https://www.w3.org/TR/xml/#charsets in log messages, NDC, and MDC property keys and values, producing invalid XML output. Conforming XML parsers must reject such documents with a fatal error, which may cause downstream log processing systems to drop or fail to index affected records. An attacker who can influence logged data can exploit this to suppress individual log records, impairing audit trails and detection of malicious activity. Users are advised to upgrade to Apache Log4cxx 1.7.0, which fixes this issue.
Affected products and versions
| Product | Affected versions | Fixed in |
|---|---|---|
| Apache Log4cxx 1.7 | earliest → < 1.7.0 | 1.7.0 |
| Apache Log4cxx (Conan) 1.7 | earliest → < 1.7.0 | 1.7.0 |
| Apache Log4cxx (Brew) 1.7 | earliest → < 1.7.0 | 1.7.0 |
References
- github.com github.com
- logging.apache.org logging.apache.org
- logging.apache.org logging.apache.org
- logging.apache.org logging.apache.org
- lists.apache.org lists.apache.org
Timeline
- Published
- Last modified
Other CVEs of Apache Log4cxx
The 4 CVEs of Apache Log4cxx →
CVE-2025-54812
Improper Output Neutralization for Logs vulnerability in Apache Log4cxx
2.1
Low
CVE-2025-54813
Improper Output Neutralization for Logs vulnerability in Apache Log4cxx
6.3
Medium
CVE-2023-31038
SQL injection in Log4cxx when using the ODBC appender to send log messages to a database. No fields sent to the…
Not rated