CVE-2026-128346
ExcelJS through 4.4.0 Resource Exhaustion via Streaming WorkbookReader Temporary Files
Description
ExcelJS through 4.4.0 contains a resource leak vulnerability in the streaming WorkbookReader.parse that leaves temporary files and open descriptors when sheet parsing fails or iteration stops early. Attackers can repeatedly upload malformed multi-sheet workbooks with worksheets placed before xl/sharedStrings.xml to fill the temporary directory and exhaust file descriptors.
INFO
Published Date :
Nov. 13, 2026, 10:18 a.m.
Last Modified :
Nov. 13, 2026, 10:18 a.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | 83251b91-4cc7-4094-a5c7-464a1b83ea10 | ||||
| CVSS 3.1 | HIGH | MITRE-CVE | ||||
| CVSS 3.1 | HIGH | [email protected] | ||||
| CVSS 4.0 | HIGH | 83251b91-4cc7-4094-a5c7-464a1b83ea10 | ||||
| CVSS 4.0 | HIGH | [email protected] |
Solution
- Update ExcelJS to version 4.4.1 or later.
- Ensure proper cleanup of temporary files.
- Handle parsing errors to prevent resource leaks.
- Validate workbook structure before processing.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-128346.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-128346 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-128346
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-128346 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-128346 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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New CVE Received by [email protected]
Nov. 13, 2026
Action Type Old Value New Value Added Description ExcelJS through 4.4.0 contains a resource leak vulnerability in the streaming WorkbookReader.parse that leaves temporary files and open descriptors when sheet parsing fails or iteration stops early. Attackers can repeatedly upload malformed multi-sheet workbooks with worksheets placed before xl/sharedStrings.xml to fill the temporary directory and exhaust file descriptors. Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Added CWE CWE-459 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/128xxx/CVE-2026-128346.json">CVE-2026-128346</a> Added Reference https://github.com/exceljs/exceljs Added Reference https://github.com/exceljs/exceljs/blob/v4.4.0/lib/stream/xlsx/workbook-reader.js#L111-L128 Added Reference https://github.com/exceljs/exceljs/blob/v4.4.0/lib/stream/xlsx/workbook-reader.js#L140-L149 Added Reference https://github.com/mateocallec/exceljs-hardened/security/advisories/GHSA-mp7v-gxhv-42h2 Added Reference https://www.vulncheck.com/advisories/exceljs-through-4.4.0-resource-exhaustion-via-streaming-workbookreader-temporary-files