Vulnerability in github.com/xuri/excelize/v2 (CVE-2026-107223)
Summary
Vulnerability in github.com/xuri/excelize/v2 (CVE-2026-107223). Risk of unauthorized operations or information disclosure. Exploitable via max. Mitigation: upgrade to 2.11.1-0.20260807015645-a54c578af309 or later.
Original description
The description as published by the source.
Summary
The max attribute of a `` element in xl/worksheets/sheetN.xml is read verbatim on open with no check against MaxColumns, and flatCols() then walks Min..Max doing a deepcopy.Copy and append per iteration. Executed: max="300000", only about 18x past the real 16384 limit, cost 46.2 s of CPU and 122 MB on a single SetColWidth call, and the growth is linear in max up to 2^31-1.
Confirmed at ae2113b (HEAD at the time of audit).
Details
col.go:547, flatCols(), with the two loops at :549 and :564:
for i := col.Min; i <= col.Max; i++ {
...
for i := column.Min; i <= column.Max; i++ { ... fc = append(fc, deepcopy.Copy(...)) }
column.Min and column.Max are plain int attributes on xmlWorksheet.go:279-280, bound straight from the file. MaxColumns is 16384 (templates.go:176) and nothing in the parse path compares against it.
The contrast that makes this an oversight rather than a design decision is inside the callers themselves. SetColWidth validates its own column argument through parseColRange, which clamps to MaxColumns. But flatCols iterates ws.Cols.Col, the file-loaded slice, so the caller's validated argument never constrains the loop. The crafted column expands no matter which column the caller touches.
The row axis has the guard this axis is missing: GHSA-h69g-9hx6-f3v4 capped checkSheet's row allocation at TotalRows, and GHSA-q5j5-6p94-4gwc capped streaming Rows.Next. There is no column-axis e…
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-2026-107223 has been found in github.com/xuri/excelize/v2.
Attackers can target a specific entry point like max over the network to misuse the product.
Risk of unauthorized operations or information disclosure. CVSS score: 7.5/10.
What to do: upgrade github.com/xuri/excelize/v2 to 2.11.1-0.20260807015645-a54c578af309 or later.
If unsure, ask your IT team or search "github.com/xuri/excelize/v2 CVE-2026-107223" on the vendor's site.
CVE-2026-107223 (github.com/xuri/excelize/v2) — CWE-789 / CVSS v3 7.5
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Attack surface: max / MaxColumns / Min..Max / deepcopy.Copy
Patched: 2.11.1-0.20260807015645-a54c578af309 — 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.
A vulnerability (CWE-789) exists in github.com/xuri/excelize/v2. Attackers reach the vulnerable code path via max without authentication.
Check the vendor advisory for the affected versions of github.com/xuri/excelize/v2. Attack surface: max / MaxColumns / Min..Max / deepcopy.Copy.
Severity: High (CVSS 7.5/10). Risk of unauthorized operations or information disclosure.
Update to 2.11.1-0.20260807015645-a54c578af309.
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 2.11.1-0.20260807015645-a54c578af309ステージング環境で 2.11.1-0.20260807015645-a54c578af309 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
- exploit security-advisories@github.com
- patch security-advisories@github.com
- patch security-advisories@github.com
- web github.com