Vulnerability database
Every flaw the U.S. government’s cybersecurity agency (CISA) has confirmed attackers are using, plus the new WordPress plugin and theme bugs published each day, sorted by what they mean for a small business. We refresh it twice a day. If you see something your website or office runs, tell us.
5 results
Aug 23, 2026exceljs through 4.4.0 fails to neutralize leading equals, plus, minus, or at signs in cell values written to CSV output.CVE-2026-78209 · Other software · exceljs · reported by VulnCheckHigh 8.4
exceljs through 4.4.0 fails to neutralize leading equals, plus, minus, or at signs in cell values written to CSV output. Attackers who can influence exported cell values can inject formulas that execute when the CSV file is opened in a spreadsheet application, potentially exfiltrating data or performing other malicious actions.
- Product
- exceljs
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Aug 23, 2026exceljs through 4.4.0 contains a path traversal vulnerability in the Workbook.addImage() function that fails to validate file paths.CVE-2026-78208 · Other software · exceljs · reported by VulnCheckHigh 8.7
exceljs through 4.4.0 contains a path traversal vulnerability in the Workbook.addImage() function that fails to validate file paths. Attackers can supply arbitrary file paths to read any file accessible to the Node.js process and embed it in the generated workbook.
- Product
- exceljs
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Aug 23, 2026exceljs through 4.4.0 contains a prototype pollution vulnerability in the deepMerge helper that fails to reject __proto__, constructor, or prototype keys when mCVE-2026-78207 · Other software · exceljs · reported by VulnCheckCritical 9.3
exceljs through 4.4.0 contains a prototype pollution vulnerability in the deepMerge helper that fails to reject __proto__, constructor, or prototype keys when merging note objects. Attackers can assign parsed JSON with a malicious __proto__ property to cell notes, modifying Object.prototype and affecting all plain objects created in the process.
- Product
- exceljs
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Aug 23, 2026exceljs through 4.4.0 decompresses all entries from supplied xlsx archives into memory without limits on entry size, total size, or compression ratio.CVE-2026-78206 · Other software · exceljs · reported by VulnCheckHigh 8.7
exceljs through 4.4.0 decompresses all entries from supplied xlsx archives into memory without limits on entry size, total size, or compression ratio. Attackers can upload highly compressed workbooks that expand to gigabytes in memory, exhausting available resources and causing denial of service.
- Product
- exceljs
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Sep 6, 2018An unescaped payload in exceljs <v1.6 allows a possible XSS via cell value when worksheet is displayed in browser.CVE-2018-16459 · Other software · https://github.com/guyonroche · reported by support@hackerone.comMedium 6.1
An unescaped payload in exceljs <v1.6 allows a possible XSS via cell value when worksheet is displayed in browser.
- Product
- exceljs
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordhackerone.comhackerone.com
Where this comes from: the exploited list is CISA’s Known Exploited Vulnerabilities catalog. Everything else is the whole National Vulnerability Database, where each record is published by the team that found the bug (Wordfence, Patchstack, WPScan, the vendors themselves and others); we show who. Exploit odds are FIRST’s EPSS, updated daily. Titles and categories are ours, so check the linked record before acting on a detail. For a write-up of the big ones, see our advisories. Every vendor, and every WordPress plugin and theme with a recorded flaw, also has its own page. All of it is free to reuse as JSON, CSV or RSS.
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