CVE-2026-39942 — directus
HIGHCVE-2026-39942 is a high-severity (CVSS 8.5) CWE-284 vulnerability in directus. A fix is available for directus — see the affected versions and patch details below.
Directus has a Path Traversal and Broken Access Control in File Management API
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-39942.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2026-39942 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,636 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
directusnpmDescription
Summary
A broken access control vulnerability was identified in the Directus file management API that allows authenticated users to overwrite files belonging to other users by manipulating the filename_disk parameter.
Details
The PATCH /files/{id} endpoint accepts a user-controlled filename_disk parameter. By setting this value to match the storage path of another user's file, an attacker can overwrite that file's content while manipulating metadata fields such as uploaded_by to obscure the tampering.
Impact
- Unauthorized File Overwrite: Attackers can replace legitimate files with malicious content, creating significant risk of malware propagation and data corruption.
- Remote Code Execution: If the storage backend is shared with the extensions location, attackers can deploy malicious extensions that execute arbitrary code when loaded.
- Data Integrity Compromise: Files can be tampered with or replaced without visible indication in the application interface.
Mitigation
The filename_disk parameter should be treated as a server-controlled value. Uniqueness of storage paths must be enforced server-side, and filename_disk should be excluded from the fields users are permitted to update directly.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | directus | all versions | 11.17.0npm install directus@11.17.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for directus, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update directus to 11.17.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-39942 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-39942 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-39942. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-39942 in your dependencies?
O3 Security finds CVE-2026-39942 across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.