by Kastro
Paper/Archive/CVE-2026-40035

CVE-2026-40035

obsidianforensics unfurl — Unfurl - Werkzeug Debugger Exposure via String Config Parsing

EPSS 0.6%public exploitCVSS 9.3
critical.is priorityof 100
47
CVSS 9.3 (CNA)9.3 / 10 × 3027.9Not in CISA KEV+300.0EPSS percentile 46.4.464 × 209.3Exploit: SSVC poc+1010.0SSVC exploitation: poc+100.0
Description · from the CVE record

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.

Affected

ProductAffectedFixed inSource
unfurl≤ 2025.08–CNA

Scores by source

VulnCheck (CNA)9.3CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
VulnCheck (CNA)9.1CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
CISA ADPSSVCExploitation: poc · Automatable: yes · Technical impact: total

References

exploitgithub.com/obsidianforensics/unfurl/security/advisories/GHSA-vg9h-jx4v-cwx2writeupvulncheck.com/advisories/dfir-unfurl-werkzeug-debugger-exposure-via-string-config-parsing