ExcelJS up to 4.4.0 xl/workbook.xml sheetId resource consumption

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.3$0-$5k0.21+

Summaryinfo

A vulnerability labeled as problematic has been found in ExcelJS up to 4.4.0. This impacts an unknown function of the file xl/workbook.xml. Such manipulation of the argument sheetId leads to resource consumption. This vulnerability is documented as CVE-2026-128342. The attack can be executed remotely. There is not any exploit available.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in ExcelJS up to 4.4.0. Affected by this issue is an unknown part of the file xl/workbook.xml. The manipulation of the argument sheetId with an unknown input leads to a resource consumption vulnerability. Using CWE to declare the problem leads to CWE-400. The product does not properly control the allocation and maintenance of a limited resource. Impacted is availability. CVE summarizes:

ExcelJS through 4.4.0 contains a denial of service vulnerability that allows attackers to block the event loop by supplying an unbounded sheetId in xl/workbook.xml. Attackers can provide a workbook with a huge sheetId, making the sparse worksheet array walk stall worksheets, getWorksheet and writeBuffer for seconds.

The advisory is available at github.com. This vulnerability is handled as CVE-2026-128342 since 11/13/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. Technical details are known, but there is no available exploit. This vulnerability is assigned to T1499 by the MITRE ATT&CK project.

By approaching the search of inurl:xl/workbook.xml it is possible to find vulnerable targets with Google Hacking.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

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Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 6.4
VulDB Meta Temp Score: 6.3

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.5
CNA Vector (VulnCheck): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Resource consumption
CWE: CWE-400 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Google Hack: 🔒
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

11/13/2026 Advisory disclosed
11/13/2026 +0 days CVE reserved
11/13/2026 +0 days VulDB entry created
11/13/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: github.com
Status: Not defined

CNA: VulnCheck
CVE: CVE-2026-128342 (🔒)

GCVE (CVE): GCVE-0-2026-128342
GCVE (VulDB): GCVE-100-437006

Entryinfo

Created: 11/13/2026 12:27
Changes: 11/13/2026 12:27 (74)
Complete: 🔍
Cache ID: 216::103

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