CVE-2026-63276 (GCVE-0-2026-63276)

Vulnerability from cvelistv5 – Published: 2026-09-22 11:10 – Updated: 2026-09-22 12:21
VLAI
Title
Stack buffer overflow in CFF to Type 1 font conversion
Summary
LibreOffice converts CFF fonts to Type 1 when it subsets a font, which happens when a document is exported to PDF, and CFF fonts may be embedded in documents. A stack buffer overflow existed in that conversion. The converted operators were written into a fixed size buffer with no check that they still fit, so a glyph emitting many operators wrote past the end of the buffer. In fixed versions the remaining capacity is tracked and the conversion stops when it is used up.
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 12:21 UTC
CWE
Assigner
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
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