CVE-2026-63276

CVE Details

Release Date:	2026-09-22
Impact:	Moderate	What is this?

Description

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.

See more information about CVE-2026-63276 from MITRE CVE dictionary and NIST NVD

NOTE: The following CVSS metrics and score provided are preliminary and subject to review.

CVSS v3 metrics

Base Score:	7.3
Vector String:	CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:H/A:H
Version:	3.1
Attack Vector:	Local
Attack Complexity:	Low
Privileges Required:	None
User Interaction:	Required
Scope:	Unchanged
Confidentiality Impact:	Low
Integrity Impact:	High
Availability Impact:	High

Errata information

Platform	Errata	Release Date
Oracle Linux version 9 (libreoffice)	ELSA-2026-82013	2026-10-13