Heap Buffer Overflow in LibreOffice Calc Affects Spreadsheet Functionality
CVE-2026-8357

5.4MEDIUM

Key Information:

Vendor

The Document Foundation

Status
Libreoffice
Vendor
CVE Published:
15 June 2026

What is CVE-2026-8357?

A vulnerability exists in LibreOffice Calc that can lead to a heap buffer overflow when opening spreadsheets with excessively long formulas. This occurs due to an insufficiently sized array that tracks the nesting depth of formulas. When the depth exceeds the allocated size, it can write beyond allocated memory, potentially leading to code execution or crashes. Updated versions have corrected this issue by resizing the array to securely accommodate the maximum nesting depth of formulas, thereby mitigating the risk.

Affected Version(s)

LibreOffice 26.2

References

https://www.libreoffice.org/about-us/security/advisories/...

CVSS V4

Score:
5.4
Severity:
MEDIUM
Confidentiality:
Low
Integrity:
Low
Availability:
High
Attack Vector:
Local
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
Unknown

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Anthropic (automated discovery using Claude)
Arthur Chan of Ada Logics (validation and reporting)
.