Out-of-Bounds Read in github.com/xuri/excelize/v2 (CVE-2026-107220)
Summary
Vulnerability in github.com/xuri/excelize/v2 (CVE-2026-107220). Risk of unauthorized operations or information disclosure. Exploitable via mergeCellsParser. Mitigation: upgrade to 2.11.1-0.20260820023833-99903a3240e5 or later.
Original description
The description as published by the source.
Summary
A worksheet containing `` makes mergeCellsParser leave the cached rectangle empty, and cellInRange then indexes that empty slice without a length check. Every non-streaming cell API panics with index out of range [0] with length 0 on the first cell read after opening the file.
Where it is
cell.go, cellInRange
func cellInRange(cell, ref []int) bool {
return cell[0] >= ref[0] && cell[0] <= ref[2] && cell[1] >= ref[1] && cell[1] <= ref[3]
}
ref is indexed at four positions with no bounds check.
The caller that can hand it an empty slice, mergeCellsParser
if ref := ws.MergeCells.Cells[i].Ref; len(ws.MergeCells.Cells[i].rect) == 0 && ref != "" {
if strings.Count(ref, ":") != 1 {
ref += ":" + ref
}
rect, err := rangeRefToCoordinates(ref)
if err != nil {
return cell, err
}
_ = sortCoordinates(rect)
ws.MergeCells.Cells[i].rect = rect
}
if cellInRange([]int{col, row}, ws.MergeCells.Cells[i].rect) {
The ref != "" condition means an empty ref skips the block that populates rect, so rect stays nil. The cellInRange call on the next line is unconditional and receives that nil slice.
Ref comes straight from xl/worksheets/sheetN.xml through encoding/xml, so an empty string is entirely attacker-controlled.
Impact
Any consumer that opens an untrusted workbook and reads a cell panics. The loop scans every merged cell, so any cell reference triggers it, not a speci…
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-107220 has been found in github.com/xuri/excelize/v2.
Attackers can target a specific entry point like mergeCellsParser over the network to misuse the product.
Risk of unauthorized operations or information disclosure. CVSS score: 6.5/10.
What to do: upgrade github.com/xuri/excelize/v2 to 2.11.1-0.20260820023833-99903a3240e5 or later.
If unsure, ask your IT team or search "github.com/xuri/excelize/v2 CVE-2026-107220" on the vendor's site.
CVE-2026-107220 (github.com/xuri/excelize/v2) — CWE-125 / CVSS v3 6.5
Attack vector: remote (network-reachable) / unauthenticated
Attack surface: mergeCellsParser / cellInRange / cell.go / ref
Patched: 2.11.1-0.20260820023833-99903a3240e5 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
Out-of-bounds read (CWE-125) exists in github.com/xuri/excelize/v2. Attackers reach the vulnerable code path via mergeCellsParser without authentication.
Check the vendor advisory for the affected versions of github.com/xuri/excelize/v2. Attack surface: mergeCellsParser / cellInRange / cell.go / ref.
Severity: Medium (CVSS 6.5/10). Risk of unauthorized operations or information disclosure.
Update to 2.11.1-0.20260820023833-99903a3240e5.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'github.com/xuri/excelize/v2' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'github.com/xuri/excelize/v2' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
github.com/xuri/excelize/v2を grep し、稼働しているサービス・バージョンを把握する。 -
2Apply patch patch
Upgrade github.com/xuri/excelize/v2 to 2.11.1-0.20260820023833-99903a3240e5ステージング環境で 2.11.1-0.20260820023833-99903a3240e5 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
-
3Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
References
- package github.com
- web github.com
- web github.com
- web github.com
- web github.com