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CVE-2026-40036 (GCVE-0-2026-40036)

Vulnerability from cvelistv5 – Published: 2026-04-08 21:35 – Updated: 2026-07-14 20:00
VLAI
Title
Unfurl < 2026.04 - Denial of Service via Unbounded zlib Decompression
Summary
Unfurl before 2026.04 contains an unbounded zlib decompression vulnerability in parse_compressed.py that allows remote attackers to cause denial of service. Attackers can submit highly compressed payloads via URL parameters to the /json/visjs endpoint that expand to gigabytes, exhausting server memory and crashing the service.
Severity
8.7 (High)
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
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: poc Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-11 03:05 UTC
CWE
  • CWE-770 - Allocation of Resources Without Limits or Throttling
  • CWE-409 - Improper Handling of Highly Compressed Data (Data Amplification)
Assigner
References
Impacted products
Vendor Product Version CPE status
obsidianforensics unfurl Affected: 0 , < 2026.04 (custom)
guessed Create a notification for this product.
Date Public
2026-01-28 00:00
Credits
Mobasi Security Team
Show details on NVD website
To clipboard 

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