Stack buffer overflow in CFF font hint handling
Summary
| CVE | CVE-2026-63275 |
|---|---|
| State | PUBLISHED |
| Assigner | Document Fdn. |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-09-22 12:17:13 UTC |
| Updated | 2026-09-22 19:09:32 UTC |
| Description | 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. |
Risk And Classification
Primary CVSS: v4.0 5.4 MEDIUM from [email protected]
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/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
EPSS: 0.001670000 probability, percentile 0.063970000 (date 2026-09-23)
Problem Types: CWE-787 | CWE-787 CWE-787 Out-of-bounds Write
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 4.0 | [email protected] | Secondary | 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/C... |
| 4.0 | CNA | CVSS | 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 |
CVSS v4.0 Breakdown
Attack Vector
LocalAttack Complexity
LowAttack Requirements
NonePrivileges Required
NoneUser Interaction
PassiveConfidentiality
LowIntegrity
LowAvailability
HighSub Conf.
NoneSub Integrity
NoneSub Availability
NoneCVSS: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/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | The Document Foundation | LibreOffice | affected 26.2 < 26.2.5 26.2 series | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| www.libreoffice.org/about-us/security/advisories/cve-2026-63275 | [email protected] | www.libreoffice.org | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: Claude, found by Anthropic using agents to study the security of open-source projects (en)
CNA: Ada Logics, validating and reporting (en)
CNA: Caolán McNamara of Collabora Productivity (en)
There are currently no legacy QID mappings associated with this CVE.