CVE-2026-40035

CRITICAL

9.1

Description

Unfurl through 2025.08 contains an improper input validation vulnerability in config parsing that enables Flask debug mode by default. The debug configuration value is read as a string and passed directly to app.run(), causing any non-empty string to evaluate truthy, allowing attackers to access the Werkzeug debugger and disclose sensitive information or achieve remote code execution.

CVE Details

CVSS v3.1 Score9.1

SeverityCRITICAL

CVSS VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Attack VectorNETWORK

ComplexityLOW

Privileges RequiredNONE

User InteractionNONE

Published4/8/2026

Last Modified4/17/2026

Sourcenvd

Honeypot Sightings0

Affected Products

ryandfir:unfurl

Weaknesses (CWE)

CWE-489

References

https://github.com/obsidianforensics/unfurl/security/advisories/GHSA-vg9h-jx4v-cwx2(disclosure@vulncheck.com)

https://www.vulncheck.com/advisories/dfir-unfurl-werkzeug-debugger-exposure-via-string-config-parsing(disclosure@vulncheck.com)

https://github.com/obsidianforensics/unfurl/security/advisories/GHSA-vg9h-jx4v-cwx2(134c704f-9b21-4f2e-91b3-4a467353bcc0)

IOC Correlations

No correlations recorded

This product uses data from the NVD API but is not endorsed or certified by the NVD.