Answer in brief
CVE-2026-128345 records a Medium severity (CVSS 6.9) vulnerability in ExcelJS through 4.4.0 ReDoS via slideFormula Shared Formula Translation. The current sources do not mark it as known exploited. The current feed maps exceljs/exceljs (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 6.9. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps exceljs/exceljs (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| exceljs/exceljsgeneric | >=0 <=4.4.0 | Not reported |
Published upstream
Nov 13, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Nov 13, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Nov 13, 2026
ExcelJS through 4.4.0 contains a regular expression denial of service vulnerability in slideFormula in lib/utils/shared-formula.js when translating shared formulas to child cells. Attackers can supply a crafted spreadsheet with very long master formulas, such as runs of hyphens, causing quadratic regex backtracking that blocks the Node.js event loop.
Quoted source text, attributed separately from HOL analysis.