Executive brief
LibreOffice, a popular open-source office productivity suite, is vulnerable to a memory corruption issue when processing certain document files. An attacker could create a malicious OOXML (DOCX) file that, when opened by a user, causes the application to crash or potentially allows for unauthorized code execution. This could lead to a loss of data or a disruption of business operations if a user is tricked into opening a specially crafted document.
Technical details
A heap buffer overflow and type confusion vulnerability exists in LibreOffice's OOXML (DOCX) import component. The flaw occurs when replaying deferred parser events for a text box element; a handler object is incorrectly assumed to be of a specific type and is written to using that type's field layout. If the actual object is smaller than the assumed type, the write operation occurs past the end of the allocated memory buffer. This out-of-bounds write is triggered via local user interaction (opening a crafted document). In fixed versions, the application performs a type check before the write operation to ensure memory safety.
Affected products
- The Document Foundation LibreOffice
Timeline
- 2026-06-15: disclosed
- 2026-06-15: advisory