CVE-2026-53752: docx4j: Stack Overflow via Cyclic `w:basedOn` Style Chain leads to Denial of Service
docx4j’s PropertyResolver and several adjacent helpers recursively walk the OpenXML style inheritance chain (w:basedOn) without cycle detection.
A WordprocessingML document containing a cyclic style chain (for example, Style A based on B and Style B based on A) causes unbounded recursion and a java.lang.StackOverflowError within the property-resolution code path.
These helpers are used by operations that require effective style resolution, including common conversion and TOC-related paths. As a result, most server-side pipelines that accept a user-supplied docx and process it through docx4j can likely be crashed by a file containing a cyclic style reference.
References
Code Behaviors & Features
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