CVE-2026-128341

Description

ExcelJS through 4.4.0 contains a resource exhaustion vulnerability in data-validations-xform.js that allows attackers to exhaust CPU and memory by supplying unbounded sqref ranges. Attackers can provide a small crafted workbook with a sqref of A1:XFD1048576 to make xlsx.load() iterate billions of addresses, blocking the event loop and crashing the process with an uncatchable out-of-memory error.

Severity scores

Each score is shown as its source gave it. They are not averaged or merged.

• 8.7CVSS 4.0, Highfrom the CNA (VulnCheck)CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
• 7.5CVSS 3.1, Highfrom the CNA (VulnCheck)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Historical context and remediation

This reference retains the original CVE publication date. A recent record update does not mean a new attack occurred.

No separately sourced impact summary is available on this page yet. Consult the description, version data and dated exploitation evidence.

No explicit remediation statement is available on this page yet. Consult the original record and vendor references before choosing a fix.

Version statuses below come from the CNA. An “unaffected” version is not necessarily a currently supported release or proof of a patch date. EPSS is a dated risk estimate, not a count of historical attacks.

Read the original CVE record.

Affected products

Timeline

1. 13 Nov 2026 Published

Weakness

• CWE-770

References

• github.comproduct
• GitHub Security Advisory (GHSA-f689-fh93-2pm2)third-party-advisory
• github.comtechnical-description
• github.comissue-tracking
• VulnCheck Advisory: ExcelJS through 4.4.0 Denial of Service via Oversized Data Validation sqrefthird-party-advisory