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CVE-2026-33017· NVD / CVE Program· CNA GitHub_M

Langflow has Unauthenticated Remote Code Execution via Public Flow Build Endpoint

Noroxi assessment

Priority: This week (action score 74/100)

  • CISA has confirmed exploitation in the wild (Mar 25, 2026). Remediation deadline for US federal agencies: Apr 8, 2026.
  • A ready-made attack module is public (Metasploit, Nuclei); exploiting it takes no special expertise.
  • Probability of exploitation in the next 30 days: 24.7% (FIRST EPSS); higher than 97.9% of all records.
  • Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
  • According to CISA the attack is automatable: targets can be found by mass scanning.
  • Fixed version: langflow-ai langflow 1.9.0.

Don’t wait for the next maintenance window. Upgrade to langflow-ai langflow 1.9.0 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · CISA KEV · FIRST EPSS

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.

CriticalCVSS 9.3 · v4.0KEVWeaponized Fix available
Published
Mar 20, 2026
Updated
Jun 17, 2026
EPSS
24.7% · 97th percentile

Report tools

JSON

Action score

74

This week

Don’t wait for the next maintenance window.

CVSS
37 / 40 · 9.3 / 10
CISA KEV
30 / 30 · Listed
EPSS
7 / 30 · 24.7%

CISA SSVC decision

Exploitation
active
Automatable
yes
Technical impact
total

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
—
CNA · GitHub_M
9.3
NVD has not scored this yet; the score shown is the CNA’s.

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:L/SI:L/SA:L

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Actively exploited in the wild

CISA added this to its Known Exploited Vulnerabilities catalog on Mar 25, 2026. That signals real attacks, not theory.

Remediation deadline for US federal agencies: Apr 8, 2026.

Get told when this record changes

  • In CISA KEV: exploitation in the wild confirmed
  • Weaponized exploit exists
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2026-33017

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
langflowlangflow

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • langflow langflowbefore 1.8.2

Versions reported by the vendor

Affected version ranges reported by the assigning authority (GitHub_M). Independent of NVD's CPE analysis and usually ahead of it.

  • langflow-ai langflow

    • < 1.9.0affected

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
PyPIlangflowbefore 1.3.01.3.0
PyPIlangflowbefore 1.9.01.9.0
PyPIlangflow-basebefore 0.3.00.3.0

Same product

langflow: all records

Other highest-scoring records for the same primary product.

  • CVE-2025-3248Langflow < 1.3.0 Unauthenticated RCE via /api/v1/validate/codeKEV
    99Now
  • CVE-2025-34291Langflow <= 1.6.9 CORS Misconfiguration to Token Hijack & RCEKEV
    95Now
  • CVE-2026-0770Langflow exec_globals Inclusion of Functionality from Untrusted Control Sphere Remote Code Execution VulnerabilityKEV
    88Now

Published before and after this one in the same product

  • ← EarlierCVE-2026-0772Jan 23, 2026 · Langflow Disk Cache Deserialization of Untrusted Data Remote Code Execution Vulnerability
    30Monitor
  • ← EarlierCVE-2026-27966Feb 25, 2026 · Langflow has Remote Code Execution in CSV Agent
    60This week
  • Later →CVE-2026-33053Mar 20, 2026 · Langflow has Missing Ownership Verification in API Key Deletion (IDOR)
    24Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
langflow-ai langflow1.9.0 · descriptionVendor (CNA)
PyPI:langflow1.3.0Package registry (OSV)
PyPI:langflow1.9.0Package registry (OSV)
PyPI:langflow-base0.3.0Package registry (OSV)

Exploit status

Weaponized

A ready exploit tool or active in-the-wild use is known for this vulnerability. This should be your top priority.

Evidence

  • Metasploit module ×1
  • Exploit-DB entry ×1
  • Nuclei detection template ×1
  • Proof-of-concept repository on GitHub ×27

Noroxi does not host or link to exploit code. Metasploit module names and Nuclei template ids are shown (names, not code); Exploit-DB entries and PoC repositories are given as counts only.

Public exploit evidence
SourceKindDate
Exploit-DB entrywebapps2026-07-08
Nuclei detection templateNuclei template CVE-2026-33017 —
Metasploit moduleexploit/multi/http/langflow_unauth_rce_cve_2026_33017Langflow Unauth RCEexploit2026-03-20
Proof-of-concept repository on GitHubstars:102026-03-21
Proof-of-concept repository on GitHubstars:12026-03-21
Proof-of-concept repository on GitHubstars:02026-03-21
Proof-of-concept repository on GitHubstars:02026-03-26
Proof-of-concept repository on GitHubstars:52026-03-27
Proof-of-concept repository on GitHubstars:112026-03-31
Proof-of-concept repository on GitHubstars:02026-04-07
Proof-of-concept repository on GitHubstars:02026-04-19
Proof-of-concept repository on GitHubstars:12026-04-20

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

  1. Metasploitsame day
  2. Published
  3. First PoC+1 d
  4. CISA KEV+5 d
  5. TodayOct 25, 2026+219 d
EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

  • CVE-2026-9198119 days apartUnauthenticated Remote Code Execution via Auto-Login Bypass and Code ValidationKEV
    78This week
  • CVE-2026-2796623 days apartLangflow has Remote Code Execution in CSV Agent
    60This week
  • CVE-2026-076856 days apartLangflow code Code Injection Remote Code Execution Vulnerability
    60This week
  • CVE-2026-10134102 days apartUnauthenticated Server-Side RCE via PythonCodeStructuredTool in Public Flows
    60This week
  • CVE-2026-93674201 days apartLangflow OSS is affected by multiple vulnerabilities
    60This week
  • CVE-2026-1056194 days apartUnauthenticated Remote Code Execution in Langflow OSS PythonREPLComponent via Builtins Injection
    40Plan

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • No account or password is required.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
Integrity
Availability
Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
X

Weakness class (CWE)

CWE-94 · Improper Control of Generation of Code ('Code Injection')

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:L/SI:L/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

nvd-secondary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

Change log

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Show all references (4 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records