CVE-2026-34480

描述

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.

如何修補 CVE-2026-34480

要修補 CVE-2026-34480,請將受影響套件升級到下列已修補版本。

• —未列出修補版本
• —未列出修補版本
• —升級至 2.25.4 或更新版本

CVE-2026-34480 正在被利用嗎?

低 — EPSS 為 0.9%,目前沒有觀察到大規模利用活動。

受影響套件(3)

• from 0
• from 0