CVE-2026-45018 Chainlit: Command injection via MCP stdio transport allows unauthenticated remote code execution

Chainlit is a Python framework for building production-ready conversational AI applications. From 2.4.0rc0 until 2.12.0, Chainlit deployments with features.mcp.enabled set to true in .chainlit/config.toml expose the POST /mcp endpoint without requiring authentication. For stdio transport, the...

CVE-2026-45018 Chainlit: Command injection via MCP stdio transport allows unauthenticated remote code execution

Chainlit is a Python framework for building production-ready conversational AI applications. From 2.4.0rc0 until 2.12.0, Chainlit deployments with features.mcp.enabled set to true in .chainlit/config.toml expose the POST /mcp endpoint without requiring authentication. For stdio transport, the...

CVE-2026-45018

Chainlit (Python framework for conversational AI applications) is vulnerable to command injection via its MCP stdio transport in versions 2.4.0rc0 through 2.12.0 . When features.mcp.enabled is set to true, the POST /mcp endpoint is exposed without authentication . The validate_mcp_command() funct...

PT-2026-81492

Name of the Vulnerable Software and Affected Versions Chainlit versions 2.4.0rc0 through 2.11.x Description Chainlit deployments with features.mcp.enabled set to true in .chainlit/config.toml expose the 'POST /mcp' endpoint without authentication. The ConnectSseMCPRequest and...

CVE-2026-45018: Improper Neutralization of Special Elements used in an OS Command

Chainlit is a Python framework for building production-ready conversational AI applications. From 2.4.0rc0 until 2.12.0, Chainlit deployments with features.mcp.enabled set to true in .chainlit/config.toml expose the POST /mcp endpoint without requiring authentication. For stdio transport, the...

CVE-2026-45019: Server-Side Request Forgery (SSRF)

Chainlit is a Python framework for building production-ready conversational AI applications. From 2.4.0rc0 until 2.12.0, Chainlit deployments with features.mcp.enabled set to true in .chainlit/config.toml expose the POST /mcp endpoint without requiring authentication. For sse and streamable-http...

PT-2026-81486

Name of the Vulnerable Software and Affected Versions Chainlit versions 2.4.0rc0 through 2.11.9 Description Deployments with features.mcp.enabled set to true in .chainlit/config.toml expose the 'POST /mcp' endpoint without authentication. For stdio transport, the endpoint accepts a user-controlle...

Chainlit contain a server-side request forgery (SSRF) vulnerability

Chainlit versions prior to 2.9.4 contain a server-side request forgery SSRF vulnerability in the /project/element update flow when configured with the SQLAlchemy data layer backend. An authenticated client can provide a user-controlled url value in an Element, which is fetched by the SQLAlchemy...

PYSEC-2026-1237 Chainlit contain a server-side request forgery (SSRF) vulnerability

Chainlit versions prior to 2.9.4 contain a server-side request forgery SSRF vulnerability in the /project/element update flow when configured with the SQLAlchemy data layer backend. An authenticated client can provide a user-controlled url value in an Element, which is fetched by the SQLAlchemy...

Chainlit contains an authorization bypass vulnerability

Chainlit versions prior to 2.8.5 contain an authorization bypass through user-controlled key vulnerability. If this vulnerability is exploited, threads may be viewed or thread ownership may be obtained by an attacker who can log in to the product...

PYSEC-2026-1238 Chainlit contains an authorization bypass vulnerability

Chainlit versions prior to 2.8.5 contain an authorization bypass through user-controlled key vulnerability. If this vulnerability is exploited, threads may be viewed or thread ownership may be obtained by an attacker who can log in to the product...

GHSA-C39V-8HRW-H448 Chainlit contains a session hijacking vulnerability

Chainlit before 2.10.1 contains a session hijacking vulnerability that allows unauthenticated attackers to restore and inherit authenticated user sessions by presenting a valid sessionId during WebSocket session restoration without ownership verification. Attackers can exploit the...

Chainlit contains a session hijacking vulnerability

Chainlit before 2.10.1 contains a session hijacking vulnerability that allows unauthenticated attackers to restore and inherit authenticated user sessions by presenting a valid sessionId during WebSocket session restoration without ownership verification. Attackers can exploit the...

Missing Authorization

Overview chainlit is a Build Conversational AI. Affected versions of this package are vulnerable to Missing Authorization via the restoreexistingsession path in the WebSocket session restoration. An attacker can gain unauthorized access to another user's session and assume their permissions and...

CVE-2026-56104

CVE-2026-56104 affects Chainlit prior to 2.10.1. A session-hijacking flaw lets unauthenticated attackers restore and inherit an authenticated user session by presenting a valid sessionId during WebSocket session restoration, without ownership verification. The attacker can exploit the restore_exi...

EUVD-2026-38285

Chainlit before 2.10.1 contains a session hijacking vulnerability that allows unauthenticated attackers to restore and inherit authenticated user sessions by presenting a valid sessionId during WebSocket session restoration without ownership verification. Attackers can exploit the...

CVE-2026-56104 Chainlit < 2.10.1 Session Hijacking via WebSocket Session Restoration

Chainlit before 2.10.1 contains a session hijacking vulnerability that allows unauthenticated attackers to restore and inherit authenticated user sessions by presenting a valid sessionId during WebSocket session restoration without ownership verification. Attackers can exploit the...

CVE-2026-56104 Chainlit < 2.10.1 Session Hijacking via WebSocket Session Restoration

Chainlit before 2.10.1 contains a session hijacking vulnerability that allows unauthenticated attackers to restore and inherit authenticated user sessions by presenting a valid sessionId during WebSocket session restoration without ownership verification. Attackers can exploit the...

CVE-2026-56104

Chainlit before 2.10.1 contains a session hijacking vulnerability that allows unauthenticated attackers to restore and inherit authenticated user sessions by presenting a valid sessionId during WebSocket session restoration without ownership verification. Attackers can exploit the...

CVE-2026-56104 Chainlit < 2.10.1 Session Hijacking via WebSocket Session Restoration

Chainlit before 2.10.1 contains a session hijacking vulnerability that allows unauthenticated attackers to restore and inherit authenticated user sessions by presenting a valid sessionId during WebSocket session restoration without ownership verification. Attackers can exploit the...