CVE-2026-9138
MEDIUM 6.5IBM Langflow OSS 1.0.0 through 1.11.2 Langflow could allow an authenticated attacker to write arbitrary files to the server due to improper input validation in the SaveToFileComponent. The application constructs local file paths using attacker‑controlled input without sufficient sanitization when handling requests to the /api/v1/run/{flow_id} endpoint. An attacker with low‑privileged authenticated access (such as a valid API key or user session) can supply crafted path values, including absolute paths or path traversal sequences, allowing arbitrary file writes to locations writable by the Langflow process. Successful exploitation may lead to unauthorized file creation or modification, potentially resulting in further compromise depending on the deployment environment.
No known exploitation, public exploit, or elevated probability at this time. Track for changes.
Exploitation likelihood
—EPSS not yet scored
Impact if exploited
6.5CVSS 3.1 · MEDIUM
- ConfidentialityNone
- IntegrityHigh
- AvailabilityNone
What an attacker needs
- ✓Access: Reachable over the network — no local access needed
- ⚠Privileges: Requires a low-privilege account
- ✓User interaction: No user interaction needed
- ✓Complexity: No special conditions — reliably repeatable
✓ lowers the bar for an attacker · ⚠ raises it
Proof of concept & exploit code
- github-search Search GitHub for public PoC repos
Test against your own equipment
curl -s https://vulnpedia.com/cve/CVE-2026-9138/poc.jsonMachine-readable PoC index for this CVE (for automation).Listed for defensive triage, patch verification, and authorized testing on systems you own. Machine-readable: /cve/CVE-2026-9138/poc.json
Weakness (CWE)
- CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
All CVSS metrics
- MEDIUM 6.5 v3.1 · CNA Primary
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N - MEDIUM 6.5 v3.1 · NVD Primary
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N