CVE-2026-63272: CWE-787 Out-of-bounds Write in The Document Foundation LibreOffice
LibreOffice can import WMF graphics, which may be embedded in documents. A heap buffer overflow existed when importing a text record that carries its own character advance widths. The count of advance values and the length of the text were read separately from the file and were not required to agree, so drawing the text walked the advance array by character position and ran past its end when the array was the shorter of the two. In fixed versions an advance array shorter than its text is ignored.
AI Analysis
Technical Summary
CVE-2026-63272 is a heap buffer overflow vulnerability in LibreOffice 26.2 related to importing WMF graphics. Specifically, when a text record includes its own character advance widths, the software reads the count of advance values and the text length separately without requiring them to match. During text rendering, the code walks the advance array by character position and can read past the end of the array if it is shorter than the text length, leading to a heap buffer overflow. The issue is fixed in later versions by ignoring advance arrays that are shorter than the text length.
Potential Impact
This vulnerability can lead to heap buffer overflow, which may cause application crashes or potentially allow an attacker to execute arbitrary code with the privileges of the user running LibreOffice. The CVSS 4.0 score is 5.4 (medium severity), reflecting local attack vector, low complexity, no privileges required, partial user interaction, and high impact on availability.
Mitigation Recommendations
No official patch or fix link is provided in the available data. Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, avoid opening untrusted WMF graphics embedded in documents to reduce risk.
CVE-2026-63272: CWE-787 Out-of-bounds Write in The Document Foundation LibreOffice
Description
LibreOffice can import WMF graphics, which may be embedded in documents. A heap buffer overflow existed when importing a text record that carries its own character advance widths. The count of advance values and the length of the text were read separately from the file and were not required to agree, so drawing the text walked the advance array by character position and ran past its end when the array was the shorter of the two. In fixed versions an advance array shorter than its text is ignored.
CVSS v4.0
Score 5.4medium
Affected software
The Document Foundation
LibreOffice
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-63272 is a heap buffer overflow vulnerability in LibreOffice 26.2 related to importing WMF graphics. Specifically, when a text record includes its own character advance widths, the software reads the count of advance values and the text length separately without requiring them to match. During text rendering, the code walks the advance array by character position and can read past the end of the array if it is shorter than the text length, leading to a heap buffer overflow. The issue is fixed in later versions by ignoring advance arrays that are shorter than the text length.
Potential Impact
This vulnerability can lead to heap buffer overflow, which may cause application crashes or potentially allow an attacker to execute arbitrary code with the privileges of the user running LibreOffice. The CVSS 4.0 score is 5.4 (medium severity), reflecting local attack vector, low complexity, no privileges required, partial user interaction, and high impact on availability.
Mitigation Recommendations
No official patch or fix link is provided in the available data. Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, avoid opening untrusted WMF graphics embedded in documents to reduce risk.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- Document Fdn.
- Date Reserved
- 2026-07-16T08:17:05.511Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6ab2677df7a7c541061982d6
Added to database: 09/22/2026, 11:33:17 UTC
Last enriched: 09/22/2026, 11:48:30 UTC
Last updated: 09/22/2026, 13:44:31 UTC
Views: 4
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