Bug 2538363 (CVE-2026-63275)

Summary:	CVE-2026-63275 libreoffice: stack buffer overflow in CFF font hint handling
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security <prodsec-ir-bot>
Status:	NEW ---	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	rhel-process-autobot, watson-tool-maintainers
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	---
Doc Text:	A flaw was found in LibreOffice. When a user opens a specially crafted document containing embedded CFF fonts, a stack-based buffer overflow can occur when reading the hints of a glyph due to improper bounds checking. This issue can cause memory corruption, resulting in an application crash.	Story Points:	---
Clone Of:		Environment:
Last Closed:		Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:	2540067
Bug Blocks:

Description OSIDB Bzimport 2026-09-22 18:17:20 UTC

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.

Comment 2 Jon Orris 2026-10-13 06:05:49 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9

Via RHSA-2026:82013 https://access.redhat.com/errata/RHSA-2026:82013

Comment 3 Jon Orris 2026-10-13 06:05:49 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9

Via RHSA-2026:82013 https://access.redhat.com/errata/RHSA-2026:82013