peter bassill · operator
$ cve CVE-2026-33017 JSON

CVE-2026-33017 KEV EXPLOIT

9.8
CRITICAL · CVSS 3.1 · EPSS 24.8% (pctl 98)

Patch first

On CISA KEV — known exploited in the wild, due 2026-04-08.

Description

Langflow is a tool for building and deploying AI-powered agents and workflows. In versions prior to 1.9.0, the POST /api/v1/build_public_tmp/{flow_id}/flow endpoint allows building public flows without requiring authentication. When the optional data parameter is supplied, the endpoint uses attacker-controlled flow data (containing arbitrary Python code in node definitions) instead of the stored flow data from the database. This code is passed to exec() with zero sandboxing, resulting in unauthenticated remote code execution. This is distinct from CVE-2025-3248, which fixed /api/v1/validate/code by adding authentication. The build_public_tmp endpoint is designed to be unauthenticated (for public flows) but incorrectly accepts attacker-supplied flow data containing arbitrary executable code. This issue has been fixed in version 1.9.0.

Scoring

CVSS9.8 (CRITICAL, v3.1)
VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS24.76% — more likely to be exploited than 98% of all CVEs
WeaknessCWE-94
On CISA KEVyes — remediate by 2026-04-08
Public exploityes
Published2026-03-20
Last modified2026-06-17

CISA KEV

NameLangflow Code Injection Vulnerability
Added2026-03-25
Due2026-04-08
Vendor / productLangflow / Langflow
Ransomware usenone reported

Affected (1)

VendorProduct
langflowlangflow

Public exploits

SourceTitleDate
exploit-dbLangflow 1.9.0 - RCE2026-07-08

References

→ the Explorer  ·  watch your stack  ·  NVD