VDB-372716 · CVE-2026-7664 · GCVE-0-2026-7664

IBM Langflow OSS up to 1.8.4 Streamable MCP Transport Endpoint improper authentication

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
8.4	$0-$5k	5.77-

Summaryinfo

A vulnerability categorized as critical has been discovered in IBM Langflow OSS up to 1.8.4. This vulnerability affects unknown code of the component Streamable MCP Transport Endpoint. Such manipulation leads to improper authentication. This vulnerability is documented as CVE-2026-7664. The attack can be executed remotely. There is not any exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability was found in IBM Langflow OSS up to 1.8.4. It has been rated as critical. Affected by this issue is an unknown functionality of the component Streamable MCP Transport Endpoint. The manipulation with an unknown input leads to a improper authentication vulnerability. Using CWE to declare the problem leads to CWE-287. When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct. Impacted is confidentiality, integrity, and availability. CVE summarizes:

IBM Langflow OSS 1.0.0 through 1.8.4 could allow unauthenticated attackers to access protected MCP project resources and execute MCP operations due to improper authorization enforcement in the Streamable MCP transport endpoint.

The advisory is shared for download at ibm.com. This vulnerability is handled as CVE-2026-7664 since 05/01/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 06/22/2026).

Upgrading eliminates this vulnerability.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Vendor

Name

Langflow OSS

Version

License

commercial

Website

Vendor: https://www.ibm.com/

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.5
VulDB Meta Temp Score: 8.4

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 9.8
CNA Vector (ibm): 🔒

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Improper authentication
CWE: CWE-287
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Timelineinfo

05/01/2026 CVE reserved
06/22/2026 +52 days Advisory disclosed
06/22/2026 +0 days VulDB entry created
06/22/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: ibm.com

Advisory: ibm.com
Status: Confirmed

CVE: CVE-2026-7664 (🔒)
GCVE (CVE): GCVE-0-2026-7664
GCVE (VulDB): GCVE-100-372716

Entryinfo

Created: 06/22/2026 18:07
Changes: 06/22/2026 18:07 (64)
Complete: 🔍
Cache ID: 216::103