CVE-2026-40036 (GCVE-0-2026-40036)
Vulnerability from cvelistv5 – Published: 2026-04-08 21:35 – Updated: 2026-11-08 14:02
VLAI
EPSS
VEX
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
SSVC
Exploitation: poc
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-11 03:05 UTC
CWE
Assigner
VulnCheck
CNA
References
3 references
| URL | Tags |
|---|---|
| https://github.com/obsidianforensics/unfurl/secur… | vendor-advisory |
| https://github.com/obsidianforensics/unfurl/relea… | release-notespatch |
| https://www.vulncheck.com/advisories/dfir-unfurl-… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| obsidianforensics | unfurl |
Affected:
0 , < 2026.04
(custom)
|
Date Public
2026-01-28 00:00
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
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.
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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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