# CVE-2026-107223: Excelize: Unbounded attribute is loaded with no MaxColumns check and expanded per-column by flatCols(), so any column mutator hangs or OOMs the process > Attackers can cause denial of service via memory exhaustion or CPU hang in Excelize by crafting spreadsheets with oversized column attributes. - **Severity:** High 7.1 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N`) - **Exploited in the wild:** Not known - **Login needed:** Not needed - **Attackable:** Over the internet - **Victim action needed:** A user has to click or open something - **Fix available:** Yes - **Published:** 7 Oct 2026 - **Updated:** 7 Oct 2026 - **Also known as:** GHSA-fq3v-74gv-27gm ## What is CVE-2026-107223? CVE-2026-107223 is a high-severity denial of service vulnerability in qax-os excelize, published on 7 Oct 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link. ### Official description Excelize is a Go language library for reading and writing Microsoft Excel spreadsheets. From 2.1.0 to 2.11.0, flatCols expands file-loaded column ranges without validating Min and Max against the worksheet column limit. SetColWidth reaches flatCols, which expands xlsxCol.Min through xlsxCol.Max without enforcing MaxColumns. When a crafted worksheet supplies an oversized col max attribute and the application invokes a column mutator, flatCols performs a deep copy and append for every attacker-selected column number, allowing an attacker to consume excessive CPU and memory or trigger OOM. No fixed version is available as of this review. Weakness: CWE-789 (Memory Allocation with Excessive Size Value) ## Which versions are affected by CVE-2026-107223? 2 open source packages ship an affected version, including github.com/xuri/excelize/v2. It affects 1 product. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `github.com/xuri/excelize/v2` | Go | From 2.1.0 | 2.11.1-0.20260807015645-a54c578af309 | | `github.com/xuri/excelize/v2` | Go | From 2.1.0 | 2.11.1-0.20260807015645-a54c578af309 | Products: Excelize Excelize. ## How do I fix CVE-2026-107223? Upgrade github.com/xuri/excelize/v2 to 2.11.1-0.20260807015645-a54c578af309 or later. ## Is CVE-2026-107223 being exploited? There is no known exploitation of CVE-2026-107223 in the wild and no public exploit code. ## Other vulnerabilities in qax-os excelize - [CVE-2026-107211](https://insights.sbomify.com/CVE-2026-107211/): Excelize: Unchecked pivot-cache field index in extractPivotTableFields causes unrecoverable panic (high 8.7) - [CVE-2026-107213](https://insights.sbomify.com/CVE-2026-107213/): Excelize: Nil-pointer dereference in GetSlicers when a worksheet has extLst present but no drawing element (high 8.7) - [CVE-2026-59161](https://insights.sbomify.com/CVE-2026-59161/): Excelize: Streaming GetRows row-bound bypass causes attacker-controlled allocation (high 8.7) - [CVE-2026-107212](https://insights.sbomify.com/CVE-2026-107212/): Excelize: Unbounded row number in Rows.Columns makes GetRows and the Rows iterator loop for days (high 7.5) - [CVE-2026-107214](https://insights.sbomify.com/CVE-2026-107214/): Excelize Decrypt: unrecoverable panics on malformed OLE/CFB encrypted workbooks (high 7.5) ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2026-107223 and fix it if it is affected. What it is: CVE-2026-107223 is a high-severity denial of service vulnerability in qax-os excelize, published on 7 Oct 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link. Exploitation: There is no known exploitation of CVE-2026-107223 in the wild and no public exploit code. Affected packages and fixed versions: - github.com/xuri/excelize/v2 (Go): affected from 2.1.0; fixed in 2.11.1-0.20260807015645-a54c578af309 - github.com/xuri/excelize/v2 (Go): affected from 2.1.0; fixed in 2.11.1-0.20260807015645-a54c578af309 Task: 1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies. 2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it. 3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead. 4. Run the tests and summarise what changed and why. 5. If nothing in the project is affected, say so and change nothing. Reference: https://insights.sbomify.com/CVE-2026-107223/ (Markdown: https://insights.sbomify.com/CVE-2026-107223/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2026-107223 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-107223 - OSV: https://osv.dev/vulnerability/CVE-2026-107223 --- From sbomify Insights: https://insights.sbomify.com/CVE-2026-107223/ Summaries are generated and may contain mistakes; the official description above is the record.