{"id":"GHSA-fx5j-qcqg-grpf","revision":"bede9b02b1b74c3ca6b0eeeaa78d9e7c","records":[{"revision":"bede9b02b1b74c3ca6b0eeeaa78d9e7c","observedAt":"2026-10-24T13:19:41.952+00:00","statement":{"source":"osv","id":"GHSA-fx5j-qcqg-grpf","aliases":["CVE-2026-59162","GO-2026-6452"],"title":"Excelize: Negative shared-string index causes panic in GetCellValue and GetRows","description":"# Negative shared-string index causes panic in GetCellValue and GetRows\n\n## Summary\n\nExcelize parses shared-string cell values with `strconv.Atoi` and checks only the upper bound before indexing the shared string slice. If an XLSX file contains a shared-string cell with `<v>-1</v>`, the parsed index is negative. The upper-bound check still passes (`len(sharedStrings) > -1`), and Excelize indexes `sharedStrings[-1]`, causing a runtime panic.\n\nThis was reproduced on the current default branch commit `1213a8bd7c5ab360554603ac5c995ccaf6eb4314` and the latest release tag `v2.10.1` (`5ad5ab3af0054c55bdce09f1530085600e9f2e45`). The issue is independent from the row-bound allocation report, so I am reporting it separately.\n\n## Affected package\n\n- Package: `github.com/xuri/excelize/v2`\n- Tested affected versions: current default branch at `1213a8bd7c5ab360554603ac5c995ccaf6eb4314`, and release `v2.10.1`\n- Fixed version: none known at the time of this report\n\n## Impact\n\nAn attacker who can provide an XLSX file to an application using Excelize can trigger a process panic when the application reads the malicious cell through common APIs such as `GetCellValue` or `GetRows`. In services that parse untrusted spreadsheets without a panic recovery boundary, this can cause denial of service.\n\n## Root cause\n\nFor shared-string cells (`t=\"s\"`), `xlsxC.getValueFrom()` parses the cell value as a shared-string index and only checks whether the index is below `len(d.SI)` before indexing:\n\n```go\nxlsxSI, _ := strconv.Atoi(strings.TrimSpace(c.V))\nif len(d.SI) > xlsxSI {\n    return d.SI[xlsxSI].String(), nil\n}\n```\n\nFor `xlsxSI == -1`, `len(d.SI) > -1` is true, so the code proceeds to index `d.SI[-1]` and panics.\n\n## Minimal worksheet payload\n\n```xml\n<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n<worksheet xmlns=\"http://schemas.openxmlformats.org/spreadsheetml/2006/main\">\n  <sheetData>\n    <row r=\"1\"><c r=\"A1\" t=\"s\"><v>-1</v></c></row>\n  </sheetData>\n</worksheet>\n```\n\nThe workbook also contains a normal `sharedStrings.xml` with one string (`ok`), so the failure is specifically due to accepting a negative index.\n\n## Reproduction\n\nCalling `GetCellValue(\"Sheet1\", \"A1\")` on the workbook panics:\n\n```text\n== negative shared string GetCellValue ==\nelapsed=0s alloc_delta=0MB\nPANIC: runtime.boundsError runtime error: index out of range [-1]\n```\n\nCalling `GetRows(\"Sheet1\")` on the same workbook also panics:\n\n```text\n== negative shared string GetRows ==\nelapsed=0s alloc_delta=0MB\nPANIC: runtime.boundsError runtime error: index out of range [-1]\n```\n\nThe same results were observed on current default branch commit `1213a8bd7c5ab360554603ac5c995ccaf6eb4314` and on release `v2.10.1`.\n\n## Expected behavior\n\nMalformed shared-string indices should be rejected or treated as missing/invalid string references without panicking.\n\n## Suggested remediation\n\nCheck both lower and upper bounds before indexing the shared string table. For example:\n\n```go\nif xlsxSI >= 0 && xlsxSI < len(d.SI) {\n    return d.SI[xlsxSI].String(), nil\n}\n```\n\nAdd regression tests for `GetCellValue()` and `GetRows()` on `t=\"s\"` cells whose `<v>` value is negative.","state":0,"publishedAt":"2026-09-10T15:08:53+00:00","modifiedAt":"2026-09-17T17:40:55.6990009+00:00","affected":[{"ecosystem":"Go","name":"github.com/xuri/excelize/v2","ranges":[{"type":"SEMVER","events":[{"kind":"introduced","version":"0"},{"kind":"fixed","version":"2.11.0"}]}],"versions":[],"rawVersionEvidence":null},{"ecosystem":"Go","name":"github.com/xuri/excelize","ranges":[{"type":"SEMVER","events":[{"kind":"introduced","version":"0"},{"kind":"last_affected","version":"1.4.0"}]}],"versions":[],"rawVersionEvidence":null}],"metrics":[{"system":"CVSS_V4","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N","score":null,"severity":null},{"system":"Publisher rating","vector":null,"score":null,"severity":"MODERATE"}],"references":["https://github.com/qax-os/excelize/security/advisories/GHSA-fx5j-qcqg-grpf","https://nvd.nist.gov/vuln/detail/CVE-2026-59162","https://github.com/qax-os/excelize/pull/2331","https://github.com/qax-os/excelize/commit/93f0b3caed37f21ef5079e3259c6c21dcfe68453","https://github.com/qax-os/excelize","https://github.com/qax-os/excelize/releases/tag/v2.11.0"],"sourceUrl":"https://github.com/advisories/GHSA-fx5j-qcqg-grpf","license":"GitHub Advisory Database · CC-BY-4.0","key":"osv:GHSA-fx5j-qcqg-grpf","identifiers":["GHSA-fx5j-qcqg-grpf","CVE-2026-59162","GO-2026-6452"]},"retained":false,"historicalAffected":[]}],"coverage":[]}