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CVE-2026-40036

CVE-2026-40036 · Unfurl < 2026.04 - Denial of Service via Unbounded zlib Decompression

This page contains facts from public vulnerability sources. Check the original advisory before updating.

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.

CVSS 8.7 · High · EPSS 0.5% · Fix available

Published
Updated

Stack: python

Affected products and versions

  • unfurl

    Versions
    • ≥ 0, < 2026.04: Affected (custom)

    Update to 2026.04

  • dfir-unfurl PyPI

    Versions
    • 20200629
    • 20200630
    • 20200630.2
    • 20200630.3
    • 20200630.4
    • 20200702
    • 20200703
    • 20200729
    • 20200812
    • 20201102
    • 20210308
    • 20210309
    • 20210310
    • 20210311
    • 20210615
    • 20220200
    • 20221100
    • 20230900
    • 20230901
    • 20240625
    • 20240626
    • 20240627
    • 20241120
    • 20241121
    • 20250218
    • 20250312
    • 20250810
    Affected ranges
    • ECOSYSTEM: < 20260405

    Update to 20260405

Original sources

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