CVE-2026-6047: CWE-787 Out-of-bounds Write in The Document Foundation LibreOffice
LibreOffice can import documents in the OOXML format (DOCX). A heap buffer overflow existed when replaying deferred parser events for a text box element. A handler object was assumed to be of one type and written to at that type's field layout, but it could be a smaller object, so the write landed past the end of the allocation. In fixed versions the type is checked before the write.
AI Analysis
Technical Summary
CVE-2026-6047 is a heap buffer overflow vulnerability in The Document Foundation's LibreOffice affecting versions 25.8 and 26.2. The flaw occurs during the import of OOXML format documents (DOCX) when replaying deferred parser events for a text box element. The software incorrectly assumes a handler object is of a certain type and writes data according to that type's field layout. However, the actual object may be smaller, causing the write operation to exceed the allocated buffer boundary. The vulnerability is addressed in fixed versions by adding a type check before performing the write operation. No official fix or patch is currently documented.
Potential Impact
Successful exploitation could lead to memory corruption due to out-of-bounds writes, potentially causing application crashes or other undefined behavior. The CVSS score of 5.4 indicates a medium severity impact. There are no known exploits in the wild at this time.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is released, users should exercise caution when opening untrusted OOXML (DOCX) documents in affected versions of LibreOffice (25.8 and 26.2).
CVE-2026-6047: CWE-787 Out-of-bounds Write in The Document Foundation LibreOffice
Description
LibreOffice can import documents in the OOXML format (DOCX). A heap buffer overflow existed when replaying deferred parser events for a text box element. A handler object was assumed to be of one type and written to at that type's field layout, but it could be a smaller object, so the write landed past the end of the allocation. In fixed versions the type is checked before the write.
CVSS v4.0
Score 5.4medium
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-6047 is a heap buffer overflow vulnerability in The Document Foundation's LibreOffice affecting versions 25.8 and 26.2. The flaw occurs during the import of OOXML format documents (DOCX) when replaying deferred parser events for a text box element. The software incorrectly assumes a handler object is of a certain type and writes data according to that type's field layout. However, the actual object may be smaller, causing the write operation to exceed the allocated buffer boundary. The vulnerability is addressed in fixed versions by adding a type check before performing the write operation. No official fix or patch is currently documented.
Potential Impact
Successful exploitation could lead to memory corruption due to out-of-bounds writes, potentially causing application crashes or other undefined behavior. The CVSS score of 5.4 indicates a medium severity impact. There are no known exploits in the wild at this time.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is released, users should exercise caution when opening untrusted OOXML (DOCX) documents in affected versions of LibreOffice (25.8 and 26.2).
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- Document Fdn.
- Date Reserved
- 2026-04-09T19:21:23.491Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a303db60b89be6888695b22
Added to database: 06/15/2026, 18:00:22 UTC
Last enriched: 06/15/2026, 18:15:23 UTC
Last updated: 07/31/2026, 19:23:00 UTC
Views: 82
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