{"api_version":"1","generated_at":"2026-11-12T07:20:11+00:00","cve":"CVE-2026-63660","urls":{"html":"https://cve.report/CVE-2026-63660","api":"https://cve.report/api/cve/CVE-2026-63660.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-63660","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-63660"},"summary":{"title":"node-fontnik: integer-overflow heap out-of-bounds write in RenderSDF","description":"node-fontnik is a library that delivers a range of glyphs rendered as SDFs (signed distance fields) in a protocol buffer. Prior to version 0.7.7, a crafted font could trigger a heap out-of-bounds write in RenderSDF (include/mapbox/glyph_foundry_impl.hpp). RenderSDF computed the SDF bitmap allocation size as buffered_width * buffered_height in 32-bit unsigned int. Glyph dimensions are derived from the uploaded font's outline bounding box with no upper bound, so a glyph large enough to make that product exceed 2³² wrapped to a small value. The buffer was then under-allocated while the render loop still wrote one byte per pixel, corrupting the heap (CWE-190 → CWE-787) and crashing the process. A 680-byte font is enough to drive FreeType to a 65536×65536 buffered glyph, wrapping the size to 0. This issue has been patched in version 0.7.7.","state":"PUBLISHED","assigner":"GitHub_M","published_at":"2026-11-11 03:16:52","updated_at":"2026-11-11 03:16:52"},"problem_types":["CWE-190","CWE-787","CWE-190 CWE-190: Integer Overflow or Wraparound","CWE-787 CWE-787: Out-of-bounds Write"],"metrics":[{"version":"3.1","source":"security-advisories@github.com","type":"Secondary","score":"8.1","severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H","data":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H","baseScore":8.1,"baseSeverity":"HIGH","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"HIGH","availabilityImpact":"HIGH"}},{"version":"3.1","source":"CNA","type":"DECLARED","score":"8.1","severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H","data":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":8.1,"baseSeverity":"HIGH","confidentialityImpact":"NONE","integrityImpact":"HIGH","privilegesRequired":"LOW","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H","version":"3.1"}}],"references":[{"url":"https://github.com/mapbox/node-fontnik/security/advisories/GHSA-cfm6-c7rv-58xj","name":"https://github.com/mapbox/node-fontnik/security/advisories/GHSA-cfm6-c7rv-58xj","refsource":"security-advisories@github.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/mapbox/node-fontnik/pull/202","name":"https://github.com/mapbox/node-fontnik/pull/202","refsource":"security-advisories@github.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/mapbox/node-fontnik/releases/tag/v0.7.7","name":"https://github.com/mapbox/node-fontnik/releases/tag/v0.7.7","refsource":"security-advisories@github.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-63660","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-63660","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"mapbox","product":"node-fontnik","version":"affected < 0.7.7","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"product":"node-fontnik","vendor":"mapbox","versions":[{"status":"affected","version":"< 0.7.7"}]}],"descriptions":[{"lang":"en","value":"node-fontnik is a library that delivers a range of glyphs rendered as SDFs (signed distance fields) in a protocol buffer. Prior to version 0.7.7, a crafted font could trigger a heap out-of-bounds write in RenderSDF (include/mapbox/glyph_foundry_impl.hpp). RenderSDF computed the SDF bitmap allocation size as buffered_width * buffered_height in 32-bit unsigned int. Glyph dimensions are derived from the uploaded font's outline bounding box with no upper bound, so a glyph large enough to make that product exceed 2³² wrapped to a small value. The buffer was then under-allocated while the render loop still wrote one byte per pixel, corrupting the heap (CWE-190 → CWE-787) and crashing the process. A 680-byte font is enough to drive FreeType to a 65536×65536 buffered glyph, wrapping the size to 0. This issue has been patched in version 0.7.7."}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":8.1,"baseSeverity":"HIGH","confidentialityImpact":"NONE","integrityImpact":"HIGH","privilegesRequired":"LOW","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-190","description":"CWE-190: Integer Overflow or Wraparound","lang":"en","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-787","description":"CWE-787: Out-of-bounds Write","lang":"en","type":"CWE"}]}],"providerMetadata":{"dateUpdated":"2026-11-11T02:40:47.419Z","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","shortName":"GitHub_M"},"references":[{"name":"https://github.com/mapbox/node-fontnik/security/advisories/GHSA-cfm6-c7rv-58xj","tags":["x_refsource_CONFIRM"],"url":"https://github.com/mapbox/node-fontnik/security/advisories/GHSA-cfm6-c7rv-58xj"},{"name":"https://github.com/mapbox/node-fontnik/pull/202","tags":["x_refsource_MISC"],"url":"https://github.com/mapbox/node-fontnik/pull/202"},{"name":"https://github.com/mapbox/node-fontnik/releases/tag/v0.7.7","tags":["x_refsource_MISC"],"url":"https://github.com/mapbox/node-fontnik/releases/tag/v0.7.7"}],"source":{"advisory":"GHSA-cfm6-c7rv-58xj","discovery":"UNKNOWN"},"title":"node-fontnik: integer-overflow heap out-of-bounds write in RenderSDF"}},"cveMetadata":{"assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","assignerShortName":"GitHub_M","cveId":"CVE-2026-63660","datePublished":"2026-11-11T02:40:47.419Z","dateReserved":"2026-07-17T14:47:08.031Z","dateUpdated":"2026-11-11T02:40:47.419Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-11-11 03:16:52","lastModifiedDate":"2026-11-11 03:16:52","problem_types":["CWE-190","CWE-787","CWE-190 CWE-190: Integer Overflow or Wraparound","CWE-787 CWE-787: Out-of-bounds Write"],"metrics":{"cvssMetricV31":[{"source":"security-advisories@github.com","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H","baseScore":8.1,"baseSeverity":"HIGH","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"HIGH","availabilityImpact":"HIGH"},"exploitabilityScore":2.8,"impactScore":5.2}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"63660","Ordinal":"1","Title":"node-fontnik: integer-overflow heap out-of-bounds write in Rende","CVE":"CVE-2026-63660","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"63660","Ordinal":"1","NoteData":"node-fontnik is a library that delivers a range of glyphs rendered as SDFs (signed distance fields) in a protocol buffer. Prior to version 0.7.7, a crafted font could trigger a heap out-of-bounds write in RenderSDF (include/mapbox/glyph_foundry_impl.hpp). RenderSDF computed the SDF bitmap allocation size as buffered_width * buffered_height in 32-bit unsigned int. Glyph dimensions are derived from the uploaded font's outline bounding box with no upper bound, so a glyph large enough to make that product exceed 2³² wrapped to a small value. The buffer was then under-allocated while the render loop still wrote one byte per pixel, corrupting the heap (CWE-190 → CWE-787) and crashing the process. A 680-byte font is enough to drive FreeType to a 65536×65536 buffered glyph, wrapping the size to 0. This issue has been patched in version 0.7.7.","Type":"Description","Title":"node-fontnik: integer-overflow heap out-of-bounds write in Rende"}]}}}