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TI-2026-28879 Aliases CVE-2026-40036GHSA-h5qv-qjv4-pc5m

Unfurl < 2026.04 - Denial of Service via Unbounded zlib Decompression

Priority HIGH 77CWE-409Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub. Impact type from CWE-770.

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00517 44th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed unfurl (obsidianforensics): 2026.04dfir-unfurl (PyPI): 20260405

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
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

VendorProductAffected versionsFixed inStatusSource
obsidianforensicsunfurlbefore 2026.042026.04Patch availableCNA
—dfir-unfurl (PyPI)before 2026040520260405Patch availableGHSA-h5qv-qjv4-pc5m
  • unfurl Vendorobsidianforensics Affected before 2026.04 Fixed in 2026.04 Patch available CNA
  • dfir-unfurl (PyPI) Vendor— Affected before 20260405 Fixed in 20260405 Patch available GHSA-h5qv-qjv4-pc5m

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:ryandfir:unfurl:*:*:*:*:*:*:*:*before 2026.04VulnerableRyandfir
  • cpe:2.3:a:ryandfir:unfurl:*:*:*:*:*:*:*:* Versions before 2026.04 Vulnerable ·Ryandfir

Remediation

  • Fix · CNA unfurl (obsidianforensics) Fixed in 2026.04
  • Fix · GHSA-h5qv-qjv4-pc5m dfir-unfurl (PyPI) Fixed in 20260405 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-40036
  2. 2026-10-03 Alias added: GHSA-h5qv-qjv4-pc5m
  3. 2026-10-25 EPSS moved to the below the 50th percentile

References

Exploit 1

Patch 1

Advisory 1

Other 4

  • TI-2026-28878 Unfurl - Werkzeug Debugger Exposure via String Config Parsing CVSS 4.0CRITICAL 9.3

Sources

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