Improper Encoding or Escaping of Output Affecting log4cxx package, versions [0,]
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Start learning- Snyk IDSNYK-CONAN-LOG4CXX-16322805
- published30 Apr 2026
- disclosed10 Apr 2026
- creditOlawale Titiloye
Introduced: 10 Apr 2026
CVE-2026-40023 (opens in a new tab)How to fix?
A fix was pushed into the master branch but not yet published.
Overview
Affected versions of this package are vulnerable to Improper Encoding or Escaping of Output in the XMLLayout component. An attacker can cause log records to be silently dropped or fail to be indexed by injecting XML 1.0 forbidden characters into logged data, which results in invalid XML output that conforming XML parsers reject with a fatal error.