CVE-2026-7663
Unauthenticated Cross-User MCP Resource Access and Tool Execution via Streamable Transport Authorization Bypass
Description
IBM Langflow OSS 1.0.0 through 1.9.6 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.
INFO
Published Date :
June 30, 2026, 8:17 p.m.
Last Modified :
July 2, 2026, 6:19 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | CRITICAL | 9a959283-ebb5-44b6-b705-dcc2bbced522 | ||||
| CVSS 3.1 | CRITICAL | MITRE-CVE | ||||
| CVSS 3.1 | CRITICAL | [email protected] | ||||
| CVSS 3.1 | CRITICAL | [email protected] |
Solution
- Update IBM Langflow to version 1.9.7 or later.
- Review and enforce authorization checks on transport endpoints.
Public PoC/Exploit Available at Github
CVE-2026-7663 has a 1 public
PoC/Exploit available at Github.
Go to the Public Exploits tab to see the list.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-7663.
| URL | Resource |
|---|---|
| https://www.ibm.com/support/pages/node/7277570 | Vendor Advisory |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-7663 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-7663
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
The Project shares all information on MCP related CVE's published
mcp mcp-security mcp-cve
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-7663 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-7663 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
Initial Analysis by [email protected]
Jul. 02, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Added CWE CWE-863 Added CPE Configuration OR *cpe:2.3:a:langflow:langflow:*:*:*:*:*:*:*:* versions from (including) 1.0.0 up to (excluding) 1.10.0 Added Reference Type IBM Corporation: https://www.ibm.com/support/pages/node/7277570 Types: Vendor Advisory -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jul. 01, 2026
Action Type Old Value New Value Changed SSVC {'id': 'CVE-2026-7663', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'yes'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-06-30T20:09:04.570606Z'} {'id': 'CVE-2026-7663', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'yes'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-06-30T00:00:00+00:00'} -
New CVE Received by [email protected]
Jun. 30, 2026
Action Type Old Value New Value Added Affected [{'cpes': ['cpe:2.3:a:ibm:langflow_oss:1.0.0:*:*:*:*:*:*:*', 'cpe:2.3:a:ibm:langflow_oss:1.9.6:*:*:*:*:*:*:*'], 'vendor': 'IBM', 'product': 'Langflow OSS', 'versions': [{'status': 'affected', 'version': '1.0.0', 'versionType': 'semver', 'lessThanOrEqual': '1.9.6'}]}] Added Description IBM Langflow OSS 1.0.0 through 1.9.6 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. Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N Added CWE CWE-285 Added Reference https://www.ibm.com/support/pages/node/7277570 -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jun. 30, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-7663', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'yes'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-06-30T20:09:04.570606Z'}