IBM Langflow Desktop Vulnerable to Remote Command Execution (CVE-2026-6543)

hello@craftedsignal.io — Thu, 30 Apr 2026 22:16:26 +0000

IBM Langflow Desktop, a tool designed to build and experiment with language models, versions 1.0.0 through 1.8.4, contains a remote command execution vulnerability (CVE-2026-6543). An attacker with the ability to influence Langflow’s execution can inject and execute arbitrary commands with the same privileges as the Langflow process. This flaw can be exploited to read sensitive environment variables containing API keys and database credentials, modify critical files, and propagate further attacks within the internal network. The vulnerability poses a significant risk to organizations utilizing affected versions of Langflow Desktop, potentially leading to data breaches and system compromise. Defenders should prioritize patching or implementing mitigations to prevent exploitation.

Attack Chain

Attacker gains initial access to a system with Langflow Desktop installed (versions 1.0.0 - 1.8.4). This could be achieved through social engineering or by compromising a user account with access to the system.
The attacker crafts a malicious input or payload designed to exploit the command execution vulnerability within Langflow.
The attacker triggers Langflow to process the malicious payload, leveraging the vulnerability to inject and execute arbitrary commands.
The injected command executes with the privileges of the Langflow process, allowing the attacker to interact with the underlying operating system.
The attacker leverages command execution to read sensitive environment variables, potentially obtaining API keys, database credentials, or other sensitive information.
The attacker uses the acquired credentials to access sensitive data or systems within the internal network, escalating their privileges and expanding their reach.
The attacker modifies critical files or installs malicious software, establishing persistence and compromising the integrity of the system.
The attacker launches further attacks on the internal network, leveraging the compromised system as a pivot point to compromise additional systems and data.

Impact

Successful exploitation of CVE-2026-6543 allows attackers to execute arbitrary commands on systems running vulnerable versions of IBM Langflow Desktop. This can lead to the exposure of sensitive environment variables containing API keys and database credentials, the modification of critical files, and the launching of further attacks on the internal network. The impact can range from data breaches and system compromise to complete control over affected systems and networks. Given the nature of Langflow, targeted sectors likely include organizations involved in AI/ML development and related fields.

Recommendation

Upgrade IBM Langflow Desktop to a patched version beyond 1.8.4 to remediate CVE-2026-6543, as recommended by IBM.
Deploy the Sigma rule “Detect Langflow Process Spawning Suspicious Processes” to identify potential exploitation attempts based on unusual child processes spawned by Langflow.
Monitor network connections from Langflow Desktop instances for suspicious outbound traffic, indicating potential data exfiltration or command-and-control activity.
Implement least privilege principles to limit the impact of successful exploitation by restricting the permissions of the Langflow process.

Rclone Unauthenticated options/set Allows Runtime Auth Bypass

hello@craftedsignal.io — Thu, 23 Apr 2026 12:00:00 +0000

Rclone, a command-line program to manage files on cloud storage, is vulnerable to an authentication bypass via its remote control (RC) API. The vulnerability, present from version 1.45 onwards, stems from the options/set endpoint being exposed without authentication requirements, while still being able to modify the global runtime configuration. An unauthenticated attacker can exploit this vulnerability by setting the rc.NoAuth parameter to true, effectively disabling the authentication gate for numerous RC methods registered with AuthRequired: true. This allows unauthorized access to sensitive administrative functionality, including configuration settings and operational commands. The issue was validated against v1.73.4 and the current master branch as of April 14, 2026. This vulnerability is especially critical when the RC API is exposed without global HTTP authentication (i.e. --rc-user/--rc-pass are not set), as it allows complete control of the Rclone instance.

Attack Chain

An attacker identifies a vulnerable Rclone instance with the RC API enabled (via --rc or rclone rcd) that is reachable on the network. The attacker confirms that the RC API is not protected by global HTTP authentication (no --rc-user, --rc-pass, or --rc-htpasswd flags).
The attacker sends an unauthenticated POST request to the /options/set endpoint with a JSON payload setting rc.NoAuth to true: {"rc":{"NoAuth":true}}.
The Rclone RC server processes the request and updates the runtime configuration, disabling the authentication requirement for subsequent RC calls.
The attacker leverages the now-unprotected RC API to access sensitive configuration data using endpoints like /config/listremotes, /config/dump, or /config/get.
The attacker can list the available filesystems and remote configurations.
The attacker then uses operational endpoints such as /operations/list to list files and directories within a configured remote.
The attacker exploits the /operations/copyfile endpoint to copy files from one location to another, potentially exfiltrating sensitive data or overwriting critical files.
Finally, the attacker uses the /core/command endpoint to execute arbitrary commands on the host system, achieving complete system compromise. This endpoint utilizes the exec.Command(...) function, allowing arbitrary command execution.

Impact

Successful exploitation of this vulnerability allows an unauthenticated attacker to bypass intended access controls on the Rclone RC administrative interface. The impact ranges from sensitive configuration disclosure and filesystem enumeration to arbitrary command execution on the host system. This could lead to complete system compromise, data exfiltration, or denial of service. The vulnerability affects Rclone instances from version 1.45 up to (but not including) 1.73.5. The severity is amplified when the RC API is exposed to a wider network without proper authentication measures.

Recommendation

Upgrade Rclone to version 1.73.5 or later to patch CVE-2026-41176.
If upgrading is not immediately feasible, ensure that the Rclone RC API is protected by global HTTP authentication using the --rc-user, --rc-pass, or --rc-htpasswd flags.
Monitor network traffic for POST requests to the /options/set endpoint without authentication, indicative of exploitation attempts. Deploy the provided Sigma rule to detect this activity.
Review Rclone RC API access logs for unauthorized access to sensitive endpoints such as /config/listremotes, /config/dump, /config/get, /operations/list, /operations/copyfile, and /core/command after the /options/set endpoint has been accessed.

Command-Execution — CraftedSignal Threat Feed

IBM Langflow Desktop Vulnerable to Remote Command Execution (CVE-2026-6543)

Attack Chain

Impact

Recommendation

Rclone Unauthenticated options/set Allows Runtime Auth Bypass

Attack Chain

Impact

Recommendation