CVE-2026-63276
📛 CVE Title
Stack buffer overflow in CFF to Type 1 font conversion
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.
Overview
- State
- PUBLISHED
- Assigner (CNA)
- Document Fdn.
- CVSS severity
- MEDIUM
- CVSS score
- 5.4 / 10
- CVSS vector
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- Effective score
- 5.4 / 10 MEDIUM source: CNA overview
- CWE(s)
-
CWE-787 - Reserved
- 2026-07-16
- Published
- 2026-09-22 11:10 UTC
- Last updated
- 2026-09-22 12:21 UTC
- Source
- https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/63xxx/CVE-2026-63276.json
NVD triage scoring NVD CVE 2.0
Layer NVD adds on top of the CNA's CVE record — published / last-modified timestamps, exploitability / impact subscores, and the FIRST.org EPSS probability that this CVE will be exploited in the wild in the next 30 days.
- NVD published
- 2026-09-22 12:17:13 UTC
- NVD last modified
- 2026-09-22 19:09:32 UTC
NVD / KEV / EPSS data refreshed 2026-09-23 02:47 UTC. Re-run the 🛰 Backfill from NVD button above to refresh.
European Union Vulnerability Database ENISA EUVD
ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.
- EUVD ID
-
EUVD-2026-84356 - Assigner
- Document Fdn.
- Published
- Sep 22, 2026, 11:10:32 AM
- Updated
- Sep 22, 2026, 12:21:57 PM
- EUVD base score (CVSS 4.0)
-
5.4 / 10
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 - EUVD-reported EPSS
- 0.0000
- Vendors
- The Document Foundation
- Products
-
libreoffice (26.2 << 26.2.5)
- Aliases
-
GHSA-3xpv-4h8q-pj26
ENISA 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.
EUVD references (1)
Affected products (1)
| Vendor | Product | Versions | Platforms |
|---|---|---|---|
| The Document Foundation | LibreOffice |
26.2 (affected)
|
— |
Vendor references (1)
References embedded in the original CVE record by the assigning CNA.
Web references (0)
DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.
No web references attached yet.
NVD-tagged references (1)
Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.
- https://www.libreoffice.org/about-us/security/advisories/cve-2026-63276 security@documentfoundation.org
Remediations (10)
-
web:blogs.oracle.com
For more information about the Critical Patch Update program, see the security vulnerability remediation practices page located on the Oracle Trust Center.
2026-09-23 15:45 UTC -
web:sec.cloudapps.cisco.com
On September 16, 2026 , the Cisco Product Security Incident Response Team (PSIRT) published the advisories that are listed in the following tables. To remediate these vulnerabilities, Cisco strongly recommends that customers upgrade to the fixed software that is indicated in the advisories. For more information about changes in Cisco PSIRT vulnerability disclosure, see Strengthening the ...
2026-09-23 15:45 UTC -
web:senserva.com
Every Microsoft security patch (KB) and the CVEs it fixes, with severity, CVSS, and CISA KEV status. Cross-linked to the CVE reference.
2026-09-23 15:45 UTC -
web:support.apple.com
This document describes the security content of iOS 26.6 and iPadOS 26.6.
2026-09-23 15:45 UTC -
web:support.sap.com
SAP security Patch Day Bulletin This post shares the information on security notes that remediate vulnerabilities discovered in SAP products. SAP strongly recommends that the customer visits the support portal and applies patches on priority to protect their SAP landscape. On 9th of June 2026 , SAP security patch day saw the release of 15 new security notes.
2026-09-23 15:45 UTC -
web:support.sap.com
SAP security Patch Day Bulletin This post shares the information on security notes that remediate vulnerabilities discovered in SAP products. SAP strongly recommends that the customer visits the support portal and applies patches on priority to protect their SAP landscape. On 12 th of May 2026 , SAP security patch day saw the release of 15 new security notes.
2026-09-23 15:45 UTC -
web:www.aikido.dev
None of these is a clean fix , which is why the decision on how to remediate depends on knowing what package versions are running in production and why. This post will cover how AI has accelerated CVE detection and discovery, the upgrade trap, what CVE remediation actually involves in 2026 , and how to solve the CVE remediation problem.
2026-09-23 15:45 UTC -
web:www.openhands.dev
Compare 8 automated vulnerability remediation tools for 2026 on fixes, prioritization, integrations, and deployment control.
2026-09-23 15:45 UTC -
web:www.oracle.com
This Critical Patch Update contains 481 new security patches across the product families listed below. Please note that an MOS note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at April 2026 Critical Patch Update: Executive Summary and Analysis.
2026-09-23 15:45 UTC -
web:www.oracle.com
This Critical Patch Update contains 1448 new security patches across the product families listed below. Please note that a My Oracle Support (MOS) note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at July 2026 Critical Patch Update: Executive Summary and Analysis.
2026-09-23 15:45 UTC
AI Forensic Analysis
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Raw JSON
The full cvelistV5 record. Download as CVE-2026-63276.json.
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