{"description":"Trending threats, MITRE ATT\u0026CK coverage, and detection metadata — refreshed continuously.","feed_url":"https://feed.craftedsignal.io/products/cms--5.9.18/","home_page_url":"https://feed.craftedsignal.io/","items":[{"_cs_actors":[],"_cs_cves":[],"_cs_exploited":false,"_cs_products":["cms (\u003c 4.17.12)","cms (\u003c 5.9.18)"],"_cs_severities":["high"],"_cs_tags":["craft-cms","rce","vulnerability"],"_cs_type":"advisory","_cs_vendors":["Craft CMS"],"content_html":"\u003cp\u003eCraft CMS versions before 4.17.12 and 5.9.18 are vulnerable to authenticated remote code execution. The vulnerability stems from an input-handling flaw in a Yii object creation path, allowing any authenticated user to inject malicious configuration and execute arbitrary commands on the server. This is achieved by exploiting the dynamic object configuration feature of Yii, which Craft CMS utilizes to build parts of itself from a settings list. This vulnerability is related to a previously disclosed issue (GHSA-255j-qw47-wjh5) but utilizes a different, unmitigated path. The attack exploits the condition field layouts data conversion to a live FieldLayout object without proper sanitization.\u003c/p\u003e\n\u003ch2 id=\"attack-chain\"\u003eAttack Chain\u003c/h2\u003e\n\u003col\u003e\n\u003cli\u003eAn authenticated user logs into the Craft CMS admin panel.\u003c/li\u003e\n\u003cli\u003eThe attacker crafts a malicious POST request to \u003ccode\u003e/admin/actions/element-search/search\u003c/code\u003e with a JSON payload.\u003c/li\u003e\n\u003cli\u003eThe JSON payload contains a \u003ccode\u003econdition\u003c/code\u003e parameter with a nested \u003ccode\u003efieldLayouts\u003c/code\u003e array.\u003c/li\u003e\n\u003cli\u003eWithin the \u003ccode\u003efieldLayouts\u003c/code\u003e array, the attacker injects a \u003ccode\u003eyii\\\\behaviors\\\\AttributeTypecastBehavior\u003c/code\u003e object with a \u003ccode\u003e__construct()\u003c/code\u003e method.\u003c/li\u003e\n\u003cli\u003eThe \u003ccode\u003e__construct()\u003c/code\u003e method contains the malicious configuration, including \u003ccode\u003eattributeTypes\u003c/code\u003e and \u003ccode\u003etypecastBeforeSave\u003c/code\u003e parameters.\u003c/li\u003e\n\u003cli\u003eThe \u003ccode\u003etypecastBeforeSave\u003c/code\u003e parameter is configured to execute a shell command (e.g., using \u003ccode\u003e/bin/bash -c\u003c/code\u003e).\u003c/li\u003e\n\u003cli\u003eThe server-side application processes the request and attempts to create a FieldLayout object from the provided configuration data.\u003c/li\u003e\n\u003cli\u003eDue to the lack of sanitization, the malicious configuration is injected during object creation, leading to the execution of the attacker-controlled command.\u003c/li\u003e\n\u003c/ol\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eSuccessful exploitation allows an attacker to execute arbitrary commands on the server with the privileges of the web server user. This can lead to complete compromise of the Craft CMS instance, including data theft, modification, or deletion. An attacker could also pivot to other systems on the network from the compromised server. There is no specific victim count or sector targeted mentioned, but any Craft CMS instance using a vulnerable version is susceptible.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003eUpgrade Craft CMS to version 4.17.12 or 5.9.18 or later to patch the vulnerability (Affected products).\u003c/li\u003e\n\u003cli\u003eDeploy the Sigma rule \u003ccode\u003eDetect Craft CMS RCE Attempt via Element Search\u003c/code\u003e to identify exploitation attempts in web server logs (rules).\u003c/li\u003e\n\u003cli\u003eMonitor POST requests to \u003ccode\u003e/admin/actions/element-search/search\u003c/code\u003e for suspicious JSON payloads, particularly those containing \u003ccode\u003eyii\\\\behaviors\\\\AttributeTypecastBehavior\u003c/code\u003e (Attack Chain).\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2024-01-02T12:00:00Z","date_published":"2024-01-02T12:00:00Z","id":"/briefs/2024-01-craft-cms-rce/","summary":"Craft CMS versions before 4.17.12 and 5.9.18 are vulnerable to authenticated remote code execution via malicious behavior injection in the field layout hydration path.","title":"Craft CMS Authenticated Remote Code Execution via Malicious Attached Behavior","url":"https://feed.craftedsignal.io/briefs/2024-01-craft-cms-rce/"}],"language":"en","title":"CraftedSignal Threat Feed — Cms (\u003c 5.9.18)","version":"https://jsonfeed.org/version/1.1"}