# CVE-2026-6047: LibreOffice heap buffer overflow in OOXML import

Source: https://junglewise.ai/threats/cve-2026-6047-libreoffice-heap-buffer-overflow-in-ooxml-import  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-06-15. Updated: 2026-06-15  
License: CC BY 4.0 with a link back

CVE-2026-6047 · Severity: info · CVSS 5.4 · Published 2026-06-15

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.

Technologies: [The Document Foundation LibreOffice](https://junglewise.ai/threats/technologies/libreoffice). Vendors: [The Document Foundation](https://junglewise.ai/threats/vendors/the-document-foundation).

## Quick answers

**Is CVE-2026-6047 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-6047 being exploited in the wild.

**How severe is CVE-2026-6047?** Informational severity, with a CVSS score of 5.4, published 15 June 2026.

**Which products and versions are affected?** The Document Foundation LibreOffice.

**Is there a fix for CVE-2026-6047?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-6047 attacked?** It is attacked with local access, in a network appliance.

**Am I affected by CVE-2026-6047?** Check whether you run The Document Foundation LibreOffice. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## 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

## References

- [https://www.libreoffice.org/about-us/security/advisories/cve-2026-6047](https://www.libreoffice.org/about-us/security/advisories/cve-2026-6047)

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