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CVE-2026-5027 (GCVE-0-2026-5027)

Vulnerability from cvelistv5 – Published: 2026-03-27 14:54 – Updated: 2026-03-27 15:11
VLAI Shadowserver Previdian
Title
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)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
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
Impacted products
Vendor Product Version CPE status
langflow-ai langflow Affected: 0 (custom)
guessed Create a notification for this product.
Date Public
2026-03-27 16:00
Shadowserver
Known Exploited Vulnerability - GCVE BCP-07 Compliant
KEV entry ID: fcecfeec-83e7-4b34-9b3e-0f84eeb1e137

Vulnerability ID: CVE-2026-5027

Status: Confirmed

Status Updated: 2026-07-10 15:37 UTC

Exploited: Yes

Timestamps
First Seen: 2026-07-10
Asserted: 2026-07-10
Last Seen: 2026-07-10
Scope
Asset Exposure: ['internet-facing']
Notes: IoT: no | In CISA KEV: no | Honeypot connections on 2026-07-10: 1
Evidence

Type: Honeypot

Signal: In The Wild Attempts

Confidence: 70%

Source: shadowserver

Details
1D 1
Iot no
Feed Shadowserver Foundation honeypot/exploited-vulnerabilities
Type http-scan
Class None
7D Avg 0
Vendor
30D Avg 0
90D Avg 0
Product
Cisa Kev no
Connections 1
Observation Date 2026-07-10
Vulnerability Class None
Vulnerability Score None
Vulnerability Severity None
References
Created: 2026-07-12 01:01 UTC | Updated: 2026-07-12 01:01 UTC
Previdian
Known Exploited Vulnerability - GCVE BCP-07 Compliant
KEV entry ID: 587a20e7-a453-432e-a04d-c31630e6139a

Vulnerability ID: CVE-2026-5027

Status: Confirmed

Status Updated: 2026-06-10 16:20 UTC

Exploited: Yes

Timestamps
First Seen: 2026-06-10
Asserted: 2026-06-10
Scope
Notes: KEVIntel entry: Langflow - Path Traversal Arbitrary File Write via upload_user_file | Affected: langflow-ai / langflow | CVSS: 8.8 (HIGH) | EPSS: 0.02289 | Used in malware: unknown | Not yet in CISA KEV: True
Evidence

Type: Public Report

Signal: Successful Exploitation

Confidence: 70%

Source: kevintel

Details
Feed KEVIntel (kevintel.com)
Title Langflow - Path Traversal Arbitrary File Write via upload_user_file
Vendor langflow-ai
Product langflow
Added Date 2026-06-10T16:20:36.494Z
Cvss Score 8.8
Epss Score 0.02289
Cvss Severity HIGH
Epss Percentile 0.80954
Used In Malware unknown
Ahead Of Cisa Kev None
Not Yet In Cisa Kev True
References
Created: 2026-06-23 14:02 UTC | Updated: 2026-07-10 06:14 UTC
Show details on NVD website
To clipboard 

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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.


Detection rules are retrieved from Rulezet.


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.