CVE-2026-63275 (GCVE-0-2026-63275)

Vulnerability from cvelistv5 – Published: 2026-09-22 11:10 – Updated: 2026-09-22 12:23
VLAI
Title
Stack buffer overflow in CFF font hint handling
Summary
LibreOffice can read CFF fonts, which may be embedded in documents. A stack buffer overflow existed when reading the hints of a glyph. The number of hints was checked against the wrong bound, so a glyph declaring more hints than the array can hold wrote past its end. In fixed versions the hint count is checked against the capacity the array really has.
Severity
5.4 (Medium)
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N/E:P
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-22 12:23 UTC
CWE
Assigner
Document Fdn. CNA
CNA scorecard C 75/100 over 21 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
The Document Foundation LibreOffice Affected: 26.2 , < < 26.2.5 (26.2 series)
guessed Create a notification for this product.
Date Public
2026-09-21 23:59
Credits
Claude, found by Anthropic using agents to study the security of open-source projects Ada Logics, validating and reporting Caolán McNamara of Collabora Productivity
Show details on NVD website
To clipboard 

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