{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-63276", "assignerOrgId": "4fe7d05b-1353-44cc-8b7a-1e416936dff2", "state": "PUBLISHED", "assignerShortName": "Document Fdn.", "dateReserved": "2026-07-16T08:17:05.512Z", "datePublished": "2026-09-22T11:10:32.057Z", "dateUpdated": "2026-09-22T12:21:57.496Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "4fe7d05b-1353-44cc-8b7a-1e416936dff2", "shortName": "Document Fdn.", "dateUpdated": "2026-09-22T11:10:32.057Z"}, "title": "Stack buffer overflow in CFF to Type 1 font conversion", "datePublic": "2026-09-21T23:59:00.000Z", "descriptions": [{"lang": "en", "value": "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.", "supportingMedia": [{"base64": false, "type": "text/html", "value": "<p>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.</p><p>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.</p><p>In fixed versions the remaining capacity is tracked and the conversion stops when it is used up.</p>"}]}], "affected": [{"vendor": "The Document Foundation", "product": "LibreOffice", "defaultStatus": "unknown", "versions": [{"status": "affected", "version": "26.2", "lessThan": "< 26.2.5", "versionType": "26.2 series"}]}], "credits": [{"lang": "en", "type": "finder", "value": "Claude, found by Anthropic using agents to study the security of open-source projects"}, {"lang": "en", "type": "analyst", "value": "Ada Logics, validating and reporting"}, {"lang": "en", "type": "remediation developer", "value": "Caol\u00e1n McNamara of Collabora Productivity"}], "problemTypes": [{"descriptions": [{"lang": "en", "cweId": "CWE-787", "description": "CWE-787 Out-of-bounds Write", "type": "CWE"}]}], "impacts": [{"capecId": "CAPEC-44", "descriptions": [{"lang": "en", "value": "CAPEC-44 Overflow Binary Resource File"}]}], "metrics": [{"format": "CVSS", "scenarios": [{"lang": "en", "value": "GENERAL"}], "cvssV4_0": {"attackVector": "LOCAL", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "NONE", "userInteraction": "PASSIVE", "vulnConfidentialityImpact": "LOW", "vulnIntegrityImpact": "LOW", "vulnAvailabilityImpact": "HIGH", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "subAvailabilityImpact": "NONE", "exploitMaturity": "PROOF_OF_CONCEPT", "Safety": "NOT_DEFINED", "Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "valueDensity": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED", "version": "4.0", "baseSeverity": "MEDIUM", "baseScore": 5.4, "vectorString": "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"}}], "references": [{"url": "https://www.libreoffice.org/about-us/security/advisories/cve-2026-63276"}], "source": {"discovery": "EXTERNAL"}, "x_generator": {"engine": "Vulnogram 1.0.2"}}, "adp": [{"metrics": [{"other": {"type": "ssvc", "content": {"timestamp": "2026-09-22T12:21:19.661928Z", "id": "CVE-2026-63276", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "partial"}], "role": "CISA Coordinator", "version": "2.0.3"}}}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-09-22T12:21:57.496Z"}}]}}

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{"affected": [{"affectedData": [{"defaultStatus": "unknown", "product": "LibreOffice", "vendor": "The Document Foundation", "versions": [{"lessThan": "< 26.2.5", "status": "affected", "version": "26.2", "versionType": "26.2 series"}]}], "source": "security@documentfoundation.org"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "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."}], "id": "CVE-2026-63276", "lastModified": "2026-09-22T12:17:13.547", "metrics": {"cvssMetricV40": [{"cvssData": {"Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "Safety": "NOT_DEFINED", "attackComplexity": "LOW", "attackRequirements": "NONE", "attackVector": "LOCAL", "availabilityRequirement": "NOT_DEFINED", "baseScore": 5.4, "baseSeverity": "MEDIUM", "confidentialityRequirement": "NOT_DEFINED", "exploitMaturity": "PROOF_OF_CONCEPT", "integrityRequirement": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "privilegesRequired": "NONE", "providerUrgency": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "userInteraction": "PASSIVE", "valueDensity": "NOT_DEFINED", "vectorString": "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", "version": "4.0", "vulnAvailabilityImpact": "HIGH", "vulnConfidentialityImpact": "LOW", "vulnIntegrityImpact": "LOW", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "source": "security@documentfoundation.org", "type": "Secondary"}]}, "published": "2026-09-22T12:17:13.547", "references": [{"source": "security@documentfoundation.org", "url": "https://www.libreoffice.org/about-us/security/advisories/cve-2026-63276"}], "sourceIdentifier": "security@documentfoundation.org", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-787"}], "source": "security@documentfoundation.org", "type": "Secondary"}]}

{}

{"created": "2026-09-22T12:30:07.844648+00:00", "updated": "2026-09-22T12:30:07.844655+00:00", "vendors": []}