CVE-2026-63275 (GCVE-0-2026-63275)

Vulnerability from cvelistv5 – Published: 2026-09-22 11:10 – Updated: 2026-09-22 12:23
VLAI
Title
Stack buffer overflow in CFF font hint handling
Summary
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.
Severity
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
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-22 12:23 UTC
CWE
Assigner
References
Impacted products
Vendor Product Version CPE status
The Document Foundation LibreOffice Affected: 26.2 , < < 26.2.5 (26.2 series)
guessed Create a notification for this product.
Date Public
2026-09-21 23:59
Credits
Claude, found by Anthropic using agents to study the security of open-source projects Ada Logics, validating and reporting Caolán McNamara of Collabora Productivity
Show details on NVD website
To clipboard 

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-63275",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-09-22T12:23:12.191155Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-09-22T12:23:37.244Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unknown",
          "product": "LibreOffice",
          "vendor": "The Document Foundation",
          "versions": [
            {
              "lessThan": "\u003c 26.2.5",
              "status": "affected",
              "version": "26.2",
              "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"
        }
      ],
      "datePublic": "2026-09-21T23:59:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "\u003cp\u003eLibreOffice can read CFF fonts, which may be embedded in documents.\u003c/p\u003e\u003cp\u003eA 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.\u003c/p\u003e\u003cp\u003eIn fixed versions the hint count is checked against the capacity the array really has.\u003c/p\u003e"
            }
          ],
          "value": "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."
        }
      ],
      "impacts": [
        {
          "capecId": "CAPEC-44",
          "descriptions": [
            {
              "lang": "en",
              "value": "CAPEC-44 Overflow Binary Resource File"
            }
          ]
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "Automatable": "NOT_DEFINED",
            "Recovery": "NOT_DEFINED",
            "Safety": "NOT_DEFINED",
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "LOCAL",
            "baseScore": 5.4,
            "baseSeverity": "MEDIUM",
            "exploitMaturity": "PROOF_OF_CONCEPT",
            "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",
            "version": "4.0",
            "vulnAvailabilityImpact": "HIGH",
            "vulnConfidentialityImpact": "LOW",
            "vulnIntegrityImpact": "LOW",
            "vulnerabilityResponseEffort": "NOT_DEFINED"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-787",
              "description": "CWE-787 Out-of-bounds Write",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-09-22T11:10:26.876Z",
        "orgId": "4fe7d05b-1353-44cc-8b7a-1e416936dff2",
        "shortName": "Document Fdn."
      },
      "references": [
        {
          "url": "https://www.libreoffice.org/about-us/security/advisories/cve-2026-63275"
        }
      ],
      "source": {
        "discovery": "EXTERNAL"
      },
      "title": "Stack buffer overflow in CFF font hint handling",
      "x_generator": {
        "engine": "Vulnogram 1.0.2"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "4fe7d05b-1353-44cc-8b7a-1e416936dff2",
    "assignerShortName": "Document Fdn.",
    "cveId": "CVE-2026-63275",
    "datePublished": "2026-09-22T11:10:26.876Z",
    "dateReserved": "2026-07-16T08:17:05.512Z",
    "dateUpdated": "2026-09-22T12:23:37.244Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-63275",
      "date": "2026-09-26",
      "epss": "0.00167",
      "percentile": "0.05365"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "defaultStatus": "unknown",
                "product": "LibreOffice",
                "vendor": "The Document Foundation",
                "versions": [
                  {
                    "lessThan": "\u003c 26.2.5",
                    "status": "affected",
                    "version": "26.2",
                    "versionType": "26.2 series"
                  }
                ]
              }
            ],
            "source": "security@documentfoundation.org"
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "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."
          }
        ],
        "id": "CVE-2026-63275",
        "lastModified": "2026-09-22T19:09:32.273",
        "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"
            }
          ],
          "ssvcV203": [
            {
              "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "ssvcData": {
                "id": "CVE-2026-63275",
                "options": [
                  {
                    "exploitation": "none"
                  },
                  {
                    "automatable": "no"
                  },
                  {
                    "technicalImpact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-09-22T12:23:12.191155Z",
                "version": "2.0.3"
              }
            }
          ]
        },
        "published": "2026-09-22T12:17:13.287",
        "references": [
          {
            "source": "security@documentfoundation.org",
            "url": "https://www.libreoffice.org/about-us/security/advisories/cve-2026-63275"
          }
        ],
        "sourceIdentifier": "security@documentfoundation.org",
        "vulnStatus": "Deferred",
        "weaknesses": [
          {
            "description": [
              {
                "lang": "en",
                "value": "CWE-787"
              }
            ],
            "source": "security@documentfoundation.org",
            "type": "Secondary"
          }
        ]
      }
    },
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-09-24T13:40:27+00:00",
      "cve": "CVE-2026-63275",
      "id": "CVE-2026-63275",
      "initial_release_date": "2026-09-22T11:10:26.876000+00:00",
      "product_status:known_affected": "670",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "libreoffice: stack buffer overflow in CFF font hint handling",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-63275.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "important",
      "current_release_date": "2026-09-23T00:24:30Z",
      "cve": "CVE-2026-63275",
      "id": "CVE-2026-63275",
      "initial_release_date": "2026-09-23T00:24:30Z",
      "product_status:known_affected": "509",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-63275",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-63275.json",
      "version": "2"
    },
    "vulnrichment": {
      "containers": {
        "adp": [
          {
            "metrics": [
              {
                "other": {
                  "content": {
                    "id": "CVE-2026-63275",
                    "options": [
                      {
                        "Exploitation": "none"
                      },
                      {
                        "Automatable": "no"
                      },
                      {
                        "Technical Impact": "partial"
                      }
                    ],
                    "role": "CISA Coordinator",
                    "timestamp": "2026-09-22T12:23:12.191155Z",
                    "version": "2.0.3"
                  },
                  "type": "ssvc"
                }
              }
            ],
            "providerMetadata": {
              "dateUpdated": "2026-09-22T12:23:29.296Z",
              "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "shortName": "CISA-ADP"
            },
            "title": "CISA ADP Vulnrichment"
          }
        ],
        "cna": {
          "affected": [
            {
              "defaultStatus": "unknown",
              "product": "LibreOffice",
              "vendor": "The Document Foundation",
              "versions": [
                {
                  "lessThan": "\u003c 26.2.5",
                  "status": "affected",
                  "version": "26.2",
                  "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"
            }
          ],
          "datePublic": "2026-09-21T23:59:00.000Z",
          "descriptions": [
            {
              "lang": "en",
              "supportingMedia": [
                {
                  "base64": false,
                  "type": "text/html",
                  "value": "\u003cp\u003eLibreOffice can read CFF fonts, which may be embedded in documents.\u003c/p\u003e\u003cp\u003eA 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.\u003c/p\u003e\u003cp\u003eIn fixed versions the hint count is checked against the capacity the array really has.\u003c/p\u003e"
                }
              ],
              "value": "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."
            }
          ],
          "impacts": [
            {
              "capecId": "CAPEC-44",
              "descriptions": [
                {
                  "lang": "en",
                  "value": "CAPEC-44 Overflow Binary Resource File"
                }
              ]
            }
          ],
          "metrics": [
            {
              "cvssV4_0": {
                "Automatable": "NOT_DEFINED",
                "Recovery": "NOT_DEFINED",
                "Safety": "NOT_DEFINED",
                "attackComplexity": "LOW",
                "attackRequirements": "NONE",
                "attackVector": "LOCAL",
                "baseScore": 5.4,
                "baseSeverity": "MEDIUM",
                "exploitMaturity": "PROOF_OF_CONCEPT",
                "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",
                "version": "4.0",
                "vulnAvailabilityImpact": "HIGH",
                "vulnConfidentialityImpact": "LOW",
                "vulnIntegrityImpact": "LOW",
                "vulnerabilityResponseEffort": "NOT_DEFINED"
              },
              "format": "CVSS",
              "scenarios": [
                {
                  "lang": "en",
                  "value": "GENERAL"
                }
              ]
            }
          ],
          "problemTypes": [
            {
              "descriptions": [
                {
                  "cweId": "CWE-787",
                  "description": "CWE-787 Out-of-bounds Write",
                  "lang": "en",
                  "type": "CWE"
                }
              ]
            }
          ],
          "providerMetadata": {
            "dateUpdated": "2026-09-22T11:10:26.876Z",
            "orgId": "4fe7d05b-1353-44cc-8b7a-1e416936dff2",
            "shortName": "Document Fdn."
          },
          "references": [
            {
              "url": "https://www.libreoffice.org/about-us/security/advisories/cve-2026-63275"
            }
          ],
          "source": {
            "discovery": "EXTERNAL"
          },
          "title": "Stack buffer overflow in CFF font hint handling",
          "x_generator": {
            "engine": "Vulnogram 1.0.2"
          }
        }
      },
      "cveMetadata": {
        "assignerOrgId": "4fe7d05b-1353-44cc-8b7a-1e416936dff2",
        "assignerShortName": "Document Fdn.",
        "cveId": "CVE-2026-63275",
        "datePublished": "2026-09-22T11:10:26.876Z",
        "dateReserved": "2026-07-16T08:17:05.512Z",
        "dateUpdated": "2026-09-22T12:23:37.244Z",
        "state": "PUBLISHED"
      },
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.