Описание
Apache Log4j Core's XmlLayout https://logging.apache.org/log4j/2.x/manual/layouts.html#XmlLayout , in versions up to and including 2.25.3, fails to sanitize characters forbidden by the XML 1.0 specification https://www.w3.org/TR/xml/#charsets producing invalid XML output whenever a log message or MDC value contains such characters. The impact depends on the StAX implementation in use:
- JRE built-in StAX: Forbidden characters are silently written to the output, producing malformed XML. Conforming parsers must reject such documents with a fatal error, which may cause downstream log-processing systems to drop the affected records.
- Alternative StAX implementations (e.g., Woodstox https://github.com/FasterXML/woodstox , a transitive dependency of the Jackson XML Dataformat module): An exception is thrown during the logging call, and the log event is never delivered to its intended appender, only to Log4j's internal status logger.
Users are advised to upgrade to Apache Log4j Core 2.25.4, which corrects this issue by sanitizing forbidden characters before XML output.
A flaw was found in Apache Log4j Core. The XmlLayout component, responsible for formatting log messages into XML, does not properly remove or replace characters that are not allowed in XML 1.0. When log messages or diagnostic information contain these forbidden characters, the resulting XML output becomes invalid. This can lead to two main issues: either systems processing these logs will fail to read the affected records, or the logging process itself will stop delivering events, both resulting in a denial of service for logging operations.
Отчет
This flaw in Apache Log4j Core's XmlLayout component can lead to a denial of service in logging operations when log messages contain characters forbidden by the XML 1.0 specification. Systems processing these logs may fail to read records or the logging process may cease event delivery, impacting monitoring and auditing capabilities in affected Red Hat products. Red Hat products in their default configurations will be able to automatically recover, but some log messages may be lost.
Меры по смягчению последствий
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Затронутые пакеты
| Платформа | Пакет | Состояние | Рекомендация | Релиз |
|---|---|---|---|---|
| Red Hat AI Inference Server | redhat-user-workloads/rhaiis-cuda-ubi9-3-2-2 | Affected | ||
| Red Hat AI Inference Server | redhat-user-workloads/rhaiis-cuda-ubi9-3-3 | Will not fix | ||
| Red Hat AMQ Broker 7 | log4j-core | Affected | ||
| Red Hat build of Apache Camel - HawtIO 4 | log4j-core | Affected | ||
| Red Hat build of Apicurio Registry 2 | log4j-core | Will not fix | ||
| Red Hat build of Apicurio Registry 3 | log4j-core | Will not fix | ||
| Red Hat build of OptaPlanner 8 | log4j-core | Affected | ||
| Red Hat Enterprise Linux 8 | log4j:2/log4j | Affected | ||
| Red Hat Enterprise Linux 8 | pki-core:10.6/resteasy | Not affected | ||
| Red Hat Enterprise Linux 8 | pki-deps:10.6/resteasy | Not affected |
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Дополнительная информация
Статус:
EPSS
5.3 Medium
CVSS3
Связанные уязвимости
Apache Log4j Core's XmlLayout https://logging.apache.org/log4j/2.x/manual/layouts.html#XmlLayout , in versions up to and including 2.25.3, fails to sanitize characters forbidden by the XML 1.0 specification https://www.w3.org/TR/xml/#charsets producing invalid XML output whenever a log message or MDC value contains such characters. The impact depends on the StAX implementation in use: * JRE built-in StAX: Forbidden characters are silently written to the output, producing malformed XML. Conforming parsers must reject such documents with a fatal error, which may cause downstream log-processing systems to drop the affected records. * Alternative StAX implementations (e.g., Woodstox https://github.com/FasterXML/woodstox , a transitive dependency of the Jackson XML Dataformat module): An exception is thrown during the logging call, and the log event is never delivered to its intended appender, only to Log4j's internal status logger. Users are advised to upgrade to Apache Log4j Core ...
Apache Log4j Core's XmlLayout https://logging.apache.org/log4j/2.x/manual/layouts.html#XmlLayout , in versions up to and including 2.25.3, fails to sanitize characters forbidden by the XML 1.0 specification https://www.w3.org/TR/xml/#charsets producing invalid XML output whenever a log message or MDC value contains such characters. The impact depends on the StAX implementation in use: * JRE built-in StAX: Forbidden characters are silently written to the output, producing malformed XML. Conforming parsers must reject such documents with a fatal error, which may cause downstream log-processing systems to drop the affected records. * Alternative StAX implementations (e.g., Woodstox https://github.com/FasterXML/woodstox , a transitive dependency of the Jackson XML Dataformat module): An exception is thrown during the logging call, and the log event is never delivered to its intended appender, only to Log4j's internal status logger. Users are advised to upgrade to Apache Log4j
Apache Log4j Core: Silent log event loss in XmlLayout due to unescaped XML 1.0 forbidden characters
Apache Log4j Core's XmlLayout https://logging.apache.org/log4j/2.x/ma ...
Apache Log4j Core: Silent log event loss in XmlLayout due to unescaped XML 1.0 forbidden characters
EPSS
5.3 Medium
CVSS3