CVE-2026-40035

CRITICAL

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.

CVSS v3.1 Score

9.1
CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
NONE
Published: 4/8/2026Modified: 4/17/2026

Related Intelligence (0)

No articles currently reference this CVE.

References (3)

https://github.com/obsidianforensics/unfurl/security/advisories/GHSA-vg9h-jx4v-cwx2ExploitVendor Advisoryhttps://www.vulncheck.com/advisories/dfir-unfurl-werkzeug-debugger-exposure-via-string-config-parsingThird Party Advisoryhttps://github.com/obsidianforensics/unfurl/security/advisories/GHSA-vg9h-jx4v-cwx2ExploitVendor Advisory