TI-2026-54392 Aliases CVE-2026-78206 GHSA-r7gv-hxj8-94c4

exceljs through 4.4.0 Uncontrolled Resource Consumption via Unbounded xlsx Decompression

MEDIUM 45CWE-409Published 2026-08-24 · Updated 2026-11-08

Key facts

Attack vector: Network
Privileges required: None
User interaction: None
Attack complexity: Low
Attack requirements: None
Impact type: —
Confidentiality · integrity · availability: None · None · High
Fix status: No fix listed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA.

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.0063 50th percentileScored 2026-11-07

Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: None
Automatable: Yes
Technical impact: Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
exceljs	exceljs	up to 4.4.0	—	No fix listed	CNA

exceljs Vendorexceljs Affected up to 4.4.0 Fixed in — No fix listed CNA

Remediation

No fixed version listed by the sources yet.

Timeline

2026-10-02 Threatist record created from CVE-2026-78206
2026-10-03 Alias added: GHSA-r7gv-hxj8-94c4
2026-10-28 EPSS moved to the 50th–90th percentile

References

Advisory 1

GitHub Security Advisory (GHSA-7cvf-3r55-r39q)

Other 2

TI-2026-54393 exceljs through 4.4.0 Prototype Pollution via deepMerge Reached From Note Serialization CVSS 4.0CRITICAL 9.3
TI-2026-54394 exceljs through 4.4.0 Path Traversal via Unvalidated addImage filename CVSS 4.0HIGH 8.7
TI-2026-54395 exceljs through 4.4.0 CSV Formula Injection via Unescaped Cell Values CVSS 4.0HIGH 8.4

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences