Excelize ColumnNameToNumber: int64 overflow yields an out-of-domain coordinate with nil error, causing negative slice index panic on r="0" rows

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No collected risk observation for these identifiers. This does not establish absence of exploitation or a zero probability.

Excelize is a Go language library for reading and writing Microsoft Excel spreadsheets. From 2.0.0 to 2.11.0 in github.com/xuri/excelize/v2 and from 1.1.0 to 1.4.1 in github.com/xuri/excelize, ColumnNameToNumber accumulates a bijective base-26 value in int64 without detecting overflow, allowing an invalid long column name to wrap to zero with no error. ColumnNameToNumber accepts the overflowing name VGWQHXLSDVIKWV, after which checkSheetR0 and xlsxWorksheet.checkRow use the wrapped column value as an index. When a crafted worksheet uses an overflowing column name in a row normalized by checkSheetR0 or checkRow, the wrapped zero column becomes a negative slice index during worksheet normalization, allowing an attacker to panic and terminate the calling process. No fixed version is available as of this review.

Source published

7 Oct 2026 18:26:55 UTC

Source modified

8 Oct 2026 16:10:25 UTC

Observed here

23 Oct 2026 15:48:27 UTC

Source terms

CVE Program Terms of Use

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CVSS 3.1 · 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Excelize is a Go language library for reading and writing Microsoft Excel spreadsheets. From 2.0.0 to 2.11.0 in github.com/xuri/excelize/v2 and from 1.1.0 to 1.4.1 in github.com/xuri/excelize, ColumnNameToNumber accumulates a bijective base-26 value in int64 without detecting overflow, allowing an invalid long column name to wrap to zero with no error. ColumnNameToNumber accepts the overflowing name VGWQHXLSDVIKWV, after which checkSheetR0 and xlsxWorksheet.checkRow use the wrapped column value as an index. When a crafted worksheet uses an overflowing column name in a row normalized by checkSheetR0 or checkRow, the wrapped zero column becomes a negative slice index during worksheet normalization, allowing an attacker to panic and terminate the calling process. No fixed version is available as of this review.

Source published

Oct 7, 2026, 6:26:55 PM (timezone not stated)

Source modified

Oct 8, 2026, 4:10:25 PM (timezone not stated)

Observed here

9 Nov 2026 13:16:34 UTC

Source terms

ENISA EUVD · source terms and attribution apply

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EUVD CVSS 3.1 · 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Excelize is a Go language library for reading and writing Microsoft Excel spreadsheets. From 2.0.0 to 2.11.0 in github.com/xuri/excelize/v2 and from 1.1.0 to 1.4.1 in github.com/xuri/excelize, ColumnNameToNumber accumulates a bijective base-26 value in int64 without detecting overflow, allowing an invalid long column name to wrap to zero with no error. ColumnNameToNumber accepts the overflowing name VGWQHXLSDVIKWV, after which checkSheetR0 and xlsxWorksheet.checkRow use the wrapped column value as an index. When a crafted worksheet uses an overflowing column name in a row normalized by checkSheetR0 or checkRow, the wrapped zero column becomes a negative slice index during worksheet normalization, allowing an attacker to panic and terminate the calling process. No fixed version is available as of this review.

Source published

7 Oct 2026 19:17:33 UTC

Source modified

13 Oct 2026 14:23:36 UTC

Observed here

25 Oct 2026 04:17:41 UTC

Source terms

NIST NVD usage terms; underlying source attribution retained

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: nvd · NIST NVD usage terms; underlying source attribution retained. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 3.1 · [email protected] · Secondary · 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

### Summary `ColumnNameToNumber` (lib.go:220-237) accumulates the bijective base-26 value of a column name in an int64 with only an upper-bound check (`col > MaxColumns`) applied after the loop and no overflow detection. A 14-letter column name whose true value is 3·2⁶⁴ — e.g. **`VGWQHXLSDVIKWV`** — wraps to `col = 0` and passes the guard, so `CellNameToCoordinates("VGWQHXLSDVIKWV1")` returns `(col=0, row=1, err=nil)`. When normalizing a `r="0"` row, `checkSheetR0` (excelize.go:417-443, called from `checkSheet` at excelize.go:405) runs its `checkRow` closure with `col = 0`: `colIdx := col - 1` becomes **-1**, and `sheetData.Row[rowIdx].C[-1]` (excelize.go:424) raises an unrecovered `panic: runtime error: index out of range [-1]`, killing the host process. ### Details - The row side of the same coordinate gate is enforced (`checkRowNum` at excelize.go:342-350 bounds `r` before the `make([]xlsxRow, row)` allocation; this includes the fix for GHSA-h69g-9hx6-f3v4 / CVE-2026-54063, present in the audited commit). The **column** side is not: `checkSheet`/`lastRowNum`/`checkSheetR0` treat `err == nil` from `CellNameToCoordinates` as proof of an in-domain coordinate (excelize.go:356, :438), which is unsound because of the wrap-around above. - The same unsound gate also feeds `ws.SheetData.Row[rowIdx].C[colNum-1]` in `xlsxWorksheet.checkRow` (rows.go:969): a row combining a valid large column (e.g. `XFD1`) with an overflowed column panics identically. - Reachable from any `workSheetReader`-based API on an attacker-supplied worksheet: `GetCellValue`, `GetCellFormula`, `SetCellValue`, `GetMergeCells`, `GetSheetDimension`, `GetColWidth`, `AddTable`, etc. - Probe on pristine master: `ColumnNameToNumber("VGWQHXLSDVIKWV")` returns `(0, nil)`. - This is a distinct root cause from GHSA-h69g-9hx6-f3v4 (row-index allocation): different mechanism (int64 wrap-around → negative index, not oversized allocation), different sink, different fix. ### PoC A standalone program (public API only) was provided to the maintainer by email (`3-column-overflow`): it builds a workbook in memory whose `xl/worksheets/sheet1.xml` contains `<sheetData><row r="0"><c r="VGWQHXLSDVIKWV1" t="inlineStr"><is><t>pwn</t></is></c></row></sheetData>` (<1 KB of attacker XML), calls `OpenReader`, then `GetCellValue("Sheet1", "A1")` → `PANIC_REPRODUCED: runtime error: index out of range [-1]` on master `ecd99d761fe0` (2026-09-08). With the proposed patch the same program prints `NO_PANIC_BLOCKED`. ### Impact A <1 KB crafted `.xlsx` crashes any service that opens a user-supplied spreadsheet and reads it — upload processing, mail-scanning pipelines, spreadsheet conversion endpoints. Remote, unauthenticated, no privileges. ### Proposed fix Bound the accumulated value inside the loop: check `col > MaxColumns` after each digit. Every digit is at least 1, so any name whose true value exceeds MaxColumns crosses the bound inside the loop, before the accumulation can wrap or overflow — this provably covers all cases, including wraps that would land back inside `[1, MaxColumns]`. A complete patch has been provided to the maintainer.

Source published

7 Oct 2026 20:23:31 UTC

Source modified

5 Nov 2026 23:25:41 UTC

Observed here

5 Nov 2026 23:38:32 UTC

Source terms

GitHub Advisory Database · CC-BY-4.0

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CVSS_V3 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Publisher rating · HIGH

Integer overflow yields an out-of-domain coordinate with nil error, causing panic in github.com/xuri/excelize

Source published

5 Nov 2026 22:53:46 UTC

Source modified

5 Nov 2026 23:15:11 UTC

Observed here

5 Nov 2026 23:38:32 UTC

Source terms

OSV · upstream source license applies

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · OSV · upstream source license applies. Source text is retained; field grouping and change labels are provided by ChangeIntel.