{"description":"Trending threats, MITRE ATT\u0026CK coverage, and detection metadata — refreshed continuously.","feed_url":"https://feed.craftedsignal.io/tags/arelle/","home_page_url":"https://feed.craftedsignal.io/","items":[{"_cs_actors":[],"_cs_cves":[{"cvss":9.8,"id":"CVE-2026-42796"}],"_cs_exploited":false,"_cs_products":["Arelle"],"_cs_severities":["critical"],"_cs_tags":["rce","arelle","vulnerability"],"_cs_type":"advisory","_cs_vendors":["Arelle"],"content_html":"\u003cp\u003eArelle versions prior to 2.39.10 are susceptible to an unauthenticated remote code execution (RCE) vulnerability. The vulnerability resides in the \u003ccode\u003e/rest/configure\u003c/code\u003e REST endpoint, which improperly handles the \u003ccode\u003eplugins\u003c/code\u003e query parameter. This parameter is forwarded to the plugin manager without proper authentication or authorization checks. An attacker can exploit this flaw by providing a URL pointing to a malicious Python file via the \u003ccode\u003eplugins\u003c/code\u003e parameter. Upon receiving this request, the Arelle webserver downloads and executes the attacker-supplied Python code within the context of the Arelle process. This grants the attacker control over the Arelle server with the same privileges as the Arelle process. This vulnerability poses a significant risk, especially in environments where Arelle servers are exposed to the internet or untrusted networks.\u003c/p\u003e\n\u003ch2 id=\"attack-chain\"\u003eAttack Chain\u003c/h2\u003e\n\u003col\u003e\n\u003cli\u003eAn unauthenticated attacker sends a crafted HTTP GET request to the \u003ccode\u003e/rest/configure\u003c/code\u003e endpoint of the Arelle web server.\u003c/li\u003e\n\u003cli\u003eThe request includes the \u003ccode\u003eplugins\u003c/code\u003e query parameter, which contains a URL pointing to a malicious Python file hosted on an attacker-controlled server.\u003c/li\u003e\n\u003cli\u003eThe Arelle web server receives the request and, without proper authentication or authorization, forwards the \u003ccode\u003eplugins\u003c/code\u003e parameter to the plugin manager.\u003c/li\u003e\n\u003cli\u003eThe plugin manager downloads the Python file from the attacker-supplied URL using standard HTTP(S) protocols.\u003c/li\u003e\n\u003cli\u003eThe Arelle process executes the downloaded Python code using the Python interpreter.\u003c/li\u003e\n\u003cli\u003eThe malicious Python code executes arbitrary commands on the Arelle server, potentially installing malware, creating reverse shells, or exfiltrating sensitive data.\u003c/li\u003e\n\u003cli\u003eThe attacker gains control of the Arelle server and can perform further actions, such as accessing internal network resources.\u003c/li\u003e\n\u003c/ol\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eSuccessful exploitation of this vulnerability allows an unauthenticated attacker to achieve remote code execution on the Arelle server. This could lead to complete compromise of the server, including sensitive data theft, malware deployment, and further lateral movement within the network. The potential impact includes data breaches, service disruption, and reputational damage. Given the severity and ease of exploitation, any Arelle instance running a version prior to 2.39.10 is at critical risk.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003eImmediately upgrade Arelle to version 2.39.10 or later to patch CVE-2026-42796.\u003c/li\u003e\n\u003cli\u003eDeploy the Sigma rule \u0026ldquo;Detect Arelle Plugin Download via REST Endpoint\u0026rdquo; to identify exploitation attempts targeting the vulnerable \u003ccode\u003e/rest/configure\u003c/code\u003e endpoint.\u003c/li\u003e\n\u003cli\u003eMonitor web server logs for suspicious requests to the \u003ccode\u003e/rest/configure\u003c/code\u003e endpoint containing the \u003ccode\u003eplugins\u003c/code\u003e parameter.\u003c/li\u003e\n\u003cli\u003eImplement network segmentation to limit the potential impact of a compromised Arelle server.\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2026-05-04T18:16:32Z","date_published":"2026-05-04T18:16:32Z","id":"/briefs/2026-05-arelle-rce/","summary":"Arelle before 2.39.10 is vulnerable to unauthenticated remote code execution via the /rest/configure REST endpoint, allowing attackers to execute arbitrary Python code by supplying a malicious URL through the plugins parameter.","title":"Arelle Unauthenticated Remote Code Execution Vulnerability","url":"https://feed.craftedsignal.io/briefs/2026-05-arelle-rce/"}],"language":"en","title":"CraftedSignal Threat Feed — Arelle","version":"https://jsonfeed.org/version/1.1"}