CVE
CVE-2026-40035
Unfurl - Werkzeug Debugger Exposure via String Config Parsing
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.
Package Versions Affected
Package Version
patch Availability
No items found.
Automatically patch vulnerabilities without upgrading
Fix Without Upgrading
Detect compatible fix
Apply safe remediation
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CVSS Version
Severity
Base Score
CVSS Version
Score Vector
C
H
U
9.3
-
4.0
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
C
H
U
0
-
C
H
U
-
Related Resources
No items found.
References
https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/40xxx/CVE-2026-40035.json, https://github.com/obsidianforensics/unfurl/security/advisories/GHSA-vg9h-jx4v-cwx2, https://nvd.nist.gov/vuln/detail/CVE-2026-40035, https://www.vulncheck.com/advisories/dfir-unfurl-werkzeug-debugger-exposure-via-string-config-parsing