CVE-2026-18729Public exploitNetwork attack vectorHinoki check available

Authenticated code execution via ungated PythonFunction tweaks

Published Aug 28, 2026 · Updated Aug 28, 2026

Code injection in IBM Langflow OSS 1.0.0 through 1.11.1 allows remote authenticated users to execute arbitrary code on the server. The PythonFunction component omits the runtime code-execution gate, while RunFlow's private tweak channel filters only the literal code field instead of applying shared code-field blocking. An authenticated flow user can therefore bypass allow_custom_components=false and run Python with the Langflow backend process's privileges.

CVSS severity8.8
High
EPSS probability0.88%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Code injection in IBM Langflow OSS 1.0.0 through 1.11.1 allows remote authenticated users to execute arbitrary code on the server. The PythonFunction component omits the runtime code-execution gate, while RunFlow's private tweak channel filters only the literal code field instead of applying shared code-field blocking. An authenticated flow user can therefore bypass allow_custom_components=false and run Python with the Langflow backend process's privileges.

The record

CVE
CVE-2026-18729
Published
Aug 28, 2026
Updated
Aug 28, 2026
Vendor
IBM
Product
Langflow OSS
Classifications
CWE-94, T1059.006
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 28, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 28, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=1.0.0 <=1.11.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

IBM · Langflow OSSversion=1.0.0 <=1.11.1

Published CVSS scores

8.8IBMCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-94Improper Control of Generation of Code ('Code Injection')
T1059.006Command and Scripting Interpreter: Python

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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