CVE-2026-8358: CWE-843 Access of Resource Using Incompatible Type ('Type Confusion') in The Document Foundation LibreOffice
A heap buffer overflow vulnerability exists in LibreOffice Calc when importing tracked changes from spreadsheet documents that reuse the same change identifier for different change types. This causes a type confusion where the importer treats one change object as a larger type, leading to out-of-bounds memory writes. The issue affects versions 25.8 and 26.2. The vulnerability has a medium severity rating with a CVSS score of 5.4. No official patch or remediation information is currently available.
AI Analysis
Technical Summary
CVE-2026-8358 is a heap buffer overflow vulnerability in LibreOffice Calc related to importing tracked changes. When a document reuses the same change identifier for two different kinds of changes, the importer misinterprets the change object type, causing it to write beyond the allocated buffer. This type confusion (CWE-843) leads to memory corruption (CWE-787). The vulnerability affects LibreOffice versions 25.8 and 26.2. According to the description, fixed versions reject records with duplicate identifiers, but no explicit patch or remediation level is provided in the available data.
Potential Impact
Successful exploitation could lead to memory corruption due to heap buffer overflow, potentially causing application crashes or other undefined behavior. The CVSS score of 5.4 indicates a medium severity impact. There is no evidence of known exploits in the wild at this time.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. The description indicates that fixed versions reject duplicate change identifiers, implying a fix exists or is planned, but no official patch or update information is provided. Users should monitor The Document Foundation advisories for updates and avoid opening untrusted documents with tracked changes until a fix is confirmed.
CVE-2026-8358: CWE-843 Access of Resource Using Incompatible Type ('Type Confusion') in The Document Foundation LibreOffice
Description
A heap buffer overflow vulnerability exists in LibreOffice Calc when importing tracked changes from spreadsheet documents that reuse the same change identifier for different change types. This causes a type confusion where the importer treats one change object as a larger type, leading to out-of-bounds memory writes. The issue affects versions 25.8 and 26.2. The vulnerability has a medium severity rating with a CVSS score of 5.4. No official patch or remediation information is currently available.
CVSS v4.0
Score 5.4medium
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-8358 is a heap buffer overflow vulnerability in LibreOffice Calc related to importing tracked changes. When a document reuses the same change identifier for two different kinds of changes, the importer misinterprets the change object type, causing it to write beyond the allocated buffer. This type confusion (CWE-843) leads to memory corruption (CWE-787). The vulnerability affects LibreOffice versions 25.8 and 26.2. According to the description, fixed versions reject records with duplicate identifiers, but no explicit patch or remediation level is provided in the available data.
Potential Impact
Successful exploitation could lead to memory corruption due to heap buffer overflow, potentially causing application crashes or other undefined behavior. The CVSS score of 5.4 indicates a medium severity impact. There is no evidence of known exploits in the wild at this time.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. The description indicates that fixed versions reject duplicate change identifiers, implying a fix exists or is planned, but no official patch or update information is provided. Users should monitor The Document Foundation advisories for updates and avoid opening untrusted documents with tracked changes until a fix is confirmed.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- Document Fdn.
- Date Reserved
- 2026-05-11T19:01:49.347Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a303db60b89be6888695b2b
Added to database: 06/15/2026, 18:00:22 UTC
Last enriched: 06/23/2026, 15:10:18 UTC
Last updated: 07/31/2026, 19:23:00 UTC
Views: 93
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