CVE-2026-5027 (GCVE-0-2026-5027)
Vulnerability from cvelistv5 – Published: 2026-03-27 14:54 – Updated: 2026-03-27 15:11Title
Langflow - Path Traversal Arbitrary File Write via upload_user_file
Summary
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 ('../').
Severity
8.8 (High)
SSVC
Exploitation: none
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-27 15:11 UTC
CWE
- CWE-22 - Improper Limitation of a Pathname to a Restricted Directory
Assigner
References
1 reference
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| langflow-ai | langflow |
Affected:
0
(custom)
|
Date Public
2026-03-27 16:00
Previdian
Known Exploited Vulnerability - GCVE BCP-07 Compliant
KEV entry ID: a01e3d88-fd49-4b75-b0ae-598a753eaba6
Exploited: Yes
Timestamps
First Seen: 2026-06-10
Asserted: 2026-06-10
Scope
Notes: Langflow - Path Traversal Arbitrary File Write via upload_user_file | Affected: Langflow-ai / langflow | CVSS: 8.8 (HIGH) | EPSS: 0.04758 | Used in malware: unknown | Not yet in CISA KEV: True
Evidence
Type: Public Report
Signal: Successful Exploitation
Confidence: 70%
Source: previdian
Details
| Feed | Previdian (previdian.com) |
|---|---|
| Title | Langflow - Path Traversal Arbitrary File Write via upload_user_file |
| Cve Id | CVE-2026-5027 |
| Vendor | Langflow-ai |
| Ghsa Id | None |
| Product | langflow |
| Added Date | 2026-06-10T16:20:36.494Z |
| Cvss Score | 8.8 |
| Epss Score | 0.04758 |
| Previous Ids | |
| Cvss Severity | HIGH |
| Virtual Patch | False |
| Cvss Estimated | False |
| Epss Percentile | 0.91611 |
| Used In Malware | unknown |
| Vulnerability Id | CVE-2026-5027 |
| Ahead Of Cisa Kev | None |
| Not Yet In Cisa Kev | True |
References
Created: 2026-10-02 09:09 CEST
| Updated: 2026-10-02 09:09 CEST
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.
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