CVE-2026-5027
Langflow - Path Traversal Arbitrary File Write via upload_user_file
The 'POST /api/v2/files' endpoint does not sanitize the 'filename' parameter from the multipart form data, allowing an attacker to write files to arbitrary locations on the filesystem using path traversal sequences ('../').
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
Langflow - Path Traversal Arbitrary File Write via upload_user_file
The 'POST /api/v2/files' endpoint does not sanitize the 'filename' parameter from the multipart form data, allowing an attacker to write files to arbitrary locations on the filesystem using path traversal sequences ('../').
- Record
CVE-2026-5027- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-22
- Updated
- 2026-11-02
EUVDEUVD-2026-16668
The 'POST /api/v2/files' endpoint does not sanitize the 'filename' parameter from the multipart form data, allowing an attacker to write files to arbitrary locations on the filesystem using path traversal sequences ('../').
- Record
EUVD-2026-16668- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-wr3v-m658-mf42
The 'POST /api/v2/files' endpoint does not sanitize the 'filename' parameter from the multipart...
The 'POST /api/v2/files' endpoint does not sanitize the 'filename' parameter from the multipart form data, allowing an attacker to write files to arbitrary locations on the filesystem using path traversal sequences ('../').
- Record
GHSA-wr3v-m658-mf42- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-22
- Updated
- 2026-11-02
NVD
The 'POST /api/v2/files' endpoint does not sanitize the 'filename' parameter from the multipart form data, allowing an attacker to write files to arbitrary locations on the filesystem using path traversal sequences ('../').
- Record
CVE-2026-5027- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-22
- Updated
- 2026-11-02
OSV
Langflow - Path Traversal Arbitrary File Write via upload_user_file
The 'POST /api/v2/files' endpoint does not sanitize the 'filename' parameter from the multipart form data, allowing an attacker to write files to arbitrary locations on the filesystem using path traversal sequences ('../').
- Record
CVE-2026-5027- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-22
- Updated
- 2026-11-02
Affected products
Public exploits
Links only. Every CVE stores no exploit code.
| Source | Link | Date |
|---|---|---|
| Exploit-DB | Langflow 1.8.4 - Path Traversal to Remote Code Execution | 2026-08-31 |
| Nuclei | Langflow <= 1.8.4 - Path Traversal to RCE via File Upload | |
| PoC in GitHub | 0xBlackash/CVE-2026-5027 | 2026-04-03 |
| PoC in GitHub | EQSTLab/CVE-2026-5027 | 2026-04-03 |
| PoC in GitHub | HORKimhab/CVE-2026-5027 | 2026-06-11 |
| PoC in GitHub | Layer-6/CVE-2026-5027-Langflow | 2026-06-10 |
| PoC in GitHub | min8282/CVE-2026-5027 | 2026-04-03 |
| PoC in GitHub | rmhowe425/POC-CVE-2026-5027 | 2026-09-02 |
| PoC in GitHub | yahiahamza/CVE-2026-5027 | 2026-04-02 |
| PoC in GitHub | yym8538/CVE-2026-5027 | 2026-08-21 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, Exploit-DB, GitHub Advisories, Nuclei, NVD, OSV, PoC in GitHub |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-5027 is a high vulnerability (CVSS 8.8) in Langflow, published March 27, 2026. Public exploit code exists. EPSS puts the chance of exploitation in the next 30 days at 40.0%, the 98th percentile. No source names a fixed version.