{"id":"CVE-2026-107218","state":"PUBLISHED","title":"Excelize: RIGHT() on supplementary-plane text slices with a negative index and panics","description":"Excelize is a Go language library for reading and writing Microsoft Excel spreadsheets. From 2.10.1 to 2.11.0, RIGHT validates the requested length with UTF-16 code-unit counts but slices a rune array using Unicode code-point counts. RIGHT reaches leftRight through CalcCellValue, where countUTF16String validates one unit but utf8.RuneCountInString supplies the slice index in another. When RIGHT evaluates supplementary-plane text with a requested character count between the rune count and UTF-16 code-unit count, the inconsistent units produce a negative rune-slice index, allowing an attacker to panic during formula evaluation. No fixed version is available as of this review.","publishedAt":"2026-10-07T18:29:38.606Z","updatedAt":"2026-10-07T22:05:36.155Z","severity":{"score":5.3,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","source":"GitHub_M"},"assigner":"GitHub_M","products":["qax-os excelize"],"affected":[{"vendor":"qax-os","product":"excelize","versions":[{"version":">= 2.10.1, <= 2.11.0","status":"affected"}]}],"references":["https://github.com/qax-os/excelize/security/advisories/GHSA-8jjq-8j9w-m2v6","https://github.com/qax-os/excelize/pull/2390","https://github.com/qax-os/excelize/commit/ecd99d761fe0489f1ed308e2f7dc2e0502d1a396"],"weaknesses":["CWE-129"],"ingestedAt":"2026-10-29T20:10:23.711Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/107xxx/CVE-2026-107218.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-107218","state":"PUBLISHED","datePublished":"2026-10-07T18:29:38.606Z","dateUpdated":"2026-10-07T22:05:36.155Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-10-07T14:34:14.816Z"},"containers":{"cna":{"title":"Excelize: RIGHT() on supplementary-plane text slices with a negative index and panics","descriptions":[{"lang":"en","value":"Excelize is a Go language library for reading and writing Microsoft Excel spreadsheets. From 2.10.1 to 2.11.0, RIGHT validates the requested length with UTF-16 code-unit counts but slices a rune array using Unicode code-point counts. RIGHT reaches leftRight through CalcCellValue, where countUTF16String validates one unit but utf8.RuneCountInString supplies the slice index in another. When RIGHT evaluates supplementary-plane text with a requested character count between the rune count and UTF-16 code-unit count, the inconsistent units produce a negative rune-slice index, allowing an attacker to panic during formula evaluation. No fixed version is available as of this review."}],"affected":[{"vendor":"qax-os","product":"excelize","versions":[{"version":">= 2.10.1, <= 2.11.0","status":"affected"}]}],"references":[{"url":"https://github.com/qax-os/excelize/security/advisories/GHSA-8jjq-8j9w-m2v6","name":"https://github.com/qax-os/excelize/security/advisories/GHSA-8jjq-8j9w-m2v6","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/qax-os/excelize/pull/2390","name":"https://github.com/qax-os/excelize/pull/2390","tags":["x_refsource_MISC"]},{"url":"https://github.com/qax-os/excelize/commit/ecd99d761fe0489f1ed308e2f7dc2e0502d1a396","name":"https://github.com/qax-os/excelize/commit/ecd99d761fe0489f1ed308e2f7dc2e0502d1a396","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"LOW","baseScore":5.3,"baseSeverity":"MEDIUM","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-129","lang":"en","description":"CWE-129: Improper Validation of Array Index","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-10-07T18:29:38.606Z"},"source":{"advisory":"GHSA-8jjq-8j9w-m2v6","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-10-07T22:03:39.825103Z","id":"CVE-2026-107218","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-07T22:05:36.155Z"}}]}}}