CVE-2026-54449
LangBot: Authenticated RCE Via MCP Configuration
Description
LangBot is a global IM bot platform designed for LLMs. In version 4.10.7 and earlier, any authenticated user can add or change an STDIO MCP server configuration without an adequate authorization boundary. In src/langbot/pkg/provider/tools/loaders/mcp.py, StdioServerParameters accepts the configured command and arguments and starts a server-side subprocess on the LangBot server. An attacker who can sign up or obtain an account can use the Extensions MCP configuration to execute arbitrary commands with the privileges of the LangBot service, enabling data disclosure, modification, and service disruption. No fixed version is available as of this review.
INFO
Published Date :
Aug. 20, 2026, 5:18 p.m.
Last Modified :
Aug. 20, 2026, 5:18 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-54449
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | [email protected] |
Solution
- Update LangBot to a secure version.
- Review and restrict MCP configuration access.
- Implement proper authorization checks.
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-2026-54449.
| URL | Resource |
|---|---|
| https://github.com/langbot-app/LangBot/security/advisories/GHSA-3pvh-63gf-j9mw | |
| https://www.ox.security/blog/mcp-supply-chain-advisory-rce-vulnerabilities-across-the-ai-ecosystem |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-54449 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-2026-54449
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).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-54449 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-54449 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.
-
New CVE Received by [email protected]
Aug. 20, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'langbot-app', 'product': 'LangBot', 'versions': [{'status': 'affected', 'version': '<= 4.10.7'}]}] Added Description LangBot is a global IM bot platform designed for LLMs. In version 4.10.7 and earlier, any authenticated user can add or change an STDIO MCP server configuration without an adequate authorization boundary. In src/langbot/pkg/provider/tools/loaders/mcp.py, StdioServerParameters accepts the configured command and arguments and starts a server-side subprocess on the LangBot server. An attacker who can sign up or obtain an account can use the Extensions MCP configuration to execute arbitrary commands with the privileges of the LangBot service, enabling data disclosure, modification, and service disruption. No fixed version is available as of this review. Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Added CWE CWE-77 Added Reference https://github.com/langbot-app/LangBot/security/advisories/GHSA-3pvh-63gf-j9mw Added Reference https://www.ox.security/blog/mcp-supply-chain-advisory-rce-vulnerabilities-across-the-ai-ecosystem