{"description":"Trending threats, MITRE ATT\u0026CK coverage, and detection metadata — refreshed continuously.","feed_url":"https://feed.craftedsignal.io/tags/cve-2026-6596/","home_page_url":"https://feed.craftedsignal.io/","items":[{"_cs_actors":[],"_cs_cves":[],"_cs_exploited":false,"_cs_products":[],"_cs_severities":["high"],"_cs_tags":["CVE-2026-6596","unrestricted-upload","langflow"],"_cs_type":"advisory","_cs_vendors":[],"content_html":"\u003cp\u003eA critical security vulnerability, identified as CVE-2026-6596, has been discovered in langflow-ai langflow, affecting versions up to 1.1.0. The vulnerability resides within the \u003ccode\u003ecreate_upload_file\u003c/code\u003e function of the \u003ccode\u003esrc/backend/base/Langflow/api/v1/endpoints.py\u003c/code\u003e file, specifically in the API Endpoint component. This flaw allows for unrestricted file uploads, potentially enabling attackers to upload and execute malicious files on the server. The vulnerability is remotely exploitable and an exploit has been publicly released, increasing the risk of widespread exploitation. The vendor was notified, but did not respond.\u003c/p\u003e\n\u003ch2 id=\"attack-chain\"\u003eAttack Chain\u003c/h2\u003e\n\u003col\u003e\n\u003cli\u003eAn attacker identifies a Langflow instance running a vulnerable version (\u0026lt;= 1.1.0).\u003c/li\u003e\n\u003cli\u003eThe attacker sends a crafted HTTP POST request to the \u003ccode\u003ecreate_upload_file\u003c/code\u003e API endpoint.\u003c/li\u003e\n\u003cli\u003eThe request includes a malicious file disguised with a permissible extension or without proper validation.\u003c/li\u003e\n\u003cli\u003eThe \u003ccode\u003ecreate_upload_file\u003c/code\u003e function fails to adequately validate the uploaded file type or size.\u003c/li\u003e\n\u003cli\u003eThe malicious file is written to the server\u0026rsquo;s file system in an accessible location.\u003c/li\u003e\n\u003cli\u003eThe attacker crafts a second request to execute the uploaded malicious file. This could involve accessing the file directly via a web browser or triggering its execution through other server-side processes.\u003c/li\u003e\n\u003cli\u003eSuccessful execution of the file grants the attacker arbitrary code execution on the server.\u003c/li\u003e\n\u003cli\u003eThe attacker leverages code execution to compromise the system, potentially leading to data exfiltration, service disruption, or further lateral movement within the network.\u003c/li\u003e\n\u003c/ol\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eSuccessful exploitation of this vulnerability could allow an attacker to gain complete control over the affected Langflow instance. This could lead to the compromise of sensitive data, disruption of services, and potential further attacks on other systems within the network. Given the ease of exploitation and the availability of a public exploit, organizations using vulnerable versions of Langflow are at significant risk. The impact would depend on the deployment and data handled by the Langflow installation.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003eUpgrade Langflow to a version higher than 1.1.0 to patch CVE-2026-6596.\u003c/li\u003e\n\u003cli\u003eImplement the Sigma rule \u003ccode\u003eDetect Suspicious File Uploads to Langflow API\u003c/code\u003e to detect exploitation attempts targeting the \u003ccode\u003ecreate_upload_file\u003c/code\u003e endpoint.\u003c/li\u003e\n\u003cli\u003eMonitor web server logs for suspicious POST requests to the \u003ccode\u003e/api/v1/upload\u003c/code\u003e endpoint, as this is the likely path for exploitation.\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2026-04-20T03:16:16Z","date_published":"2026-04-20T03:16:16Z","id":"/briefs/2026-04-langflow-unrestricted-upload/","summary":"An unrestricted file upload vulnerability in langflow-ai langflow versions up to 1.1.0 allows remote attackers to execute arbitrary code via the create_upload_file function in the API Endpoint.","title":"Langflow Unrestricted File Upload Vulnerability (CVE-2026-6596)","url":"https://feed.craftedsignal.io/briefs/2026-04-langflow-unrestricted-upload/"}],"language":"en","title":"CraftedSignal Threat Feed — CVE-2026-6596","version":"https://jsonfeed.org/version/1.1"}