CVE-2026-78206 (GCVE-0-2026-78206)
Vulnerability from cvelistv5 – Published: 2026-08-24 00:30 – Updated: 2026-11-08 14:09
VLAI
EPSS
VEX
Title
exceljs through 4.4.0 Uncontrolled Resource Consumption via Unbounded xlsx Decompression
Summary
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.
Severity
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-26 18:09 UTC
CWE
- CWE-409 - Improper Handling of Highly Compressed Data (Data Amplification)
Assigner
VulnCheck
CNA
References
4 references
| URL | Tags |
|---|---|
| https://github.com/exceljs/exceljs | product |
| https://github.com/mateocallec/exceljs-hardened/s… | third-party-advisoryvendor-advisory |
| https://github.com/exceljs/exceljs/blob/v4.4.0/li… | technical-description |
| https://www.vulncheck.com/advisories/exceljs-thro… | third-party-advisory |
Impacted products
Date Public
2026-08-23 00:00
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Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
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The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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