{"description":"Trending threats, MITRE ATT\u0026CK coverage, and detection metadata. Fed continuously.","favicon":"https://feed.craftedsignal.io/favicon-32x32.png","feed_url":"https://feed.craftedsignal.io/products/u8-cloud/feed.json","home_page_url":"https://feed.craftedsignal.io/","icon":"https://feed.craftedsignal.io/apple-touch-icon.png","items":[{"_cs_actors":[],"_cs_cpes":["cpe:2.3:a:yonyou:u8_cloud:*:*:*:*:*:*:*:*"],"_cs_cves":[{"cvss":9.8,"id":"CVE-2023-54398"}],"_cs_exploited":true,"_cs_has_poc":false,"_cs_poc_references":[],"_cs_products":["U8 Cloud"],"_cs_severities":["critical"],"_cs_tags":[],"_cs_type":"threat","_cs_vendors":["Yonyou"],"content_html":"\u003cp\u003eYonyou U8 Cloud is affected by a critical Java deserialization vulnerability, tracked as CVE-2023-54398, residing within the \u003ccode\u003enc.impl.pub.filesystem.FileManageServlet\u003c/code\u003e component. This flaw allows unauthenticated remote attackers to trigger arbitrary OS command execution by sending a crafted serialized payload in the body of an HTTP POST request. The vulnerability stems from the \u003ccode\u003edoAction\u003c/code\u003e method, which insecurely processes incoming request body data through \u003ccode\u003eObjectInputStream.readObject()\u003c/code\u003e without implementing input validation or filtering mechanisms.\u003c/p\u003e\n\u003cp\u003eThis flaw poses a severe risk to organizations, as it bypasses standard authentication controls and provides a direct pathway for full system compromise. The Shadowserver Foundation reported observing in-the-wild exploitation of this vulnerability beginning on February 13, 2025. Defenders should prioritize identifying and patching instances of Yonyou U8 Cloud to prevent unauthorized access and potential downstream impacts, such as data exfiltration or the deployment of secondary malware payloads.\u003c/p\u003e\n\u003ch2 id=\"attack-chain\"\u003eAttack Chain\u003c/h2\u003e\n\u003col\u003e\n\u003cli\u003eAttacker performs reconnaissance to identify internet-facing Yonyou U8 Cloud instances.\u003c/li\u003e\n\u003cli\u003eAttacker probes for the presence of the vulnerable \u003ccode\u003eFileManageServlet\u003c/code\u003e endpoint.\u003c/li\u003e\n\u003cli\u003eAttacker crafts a malicious serialized Java object payload designed to execute OS commands.\u003c/li\u003e\n\u003cli\u003eAttacker sends an HTTP POST request containing the serialized payload to the \u003ccode\u003edoAction\u003c/code\u003e method of the target servlet.\u003c/li\u003e\n\u003cli\u003eThe application component \u003ccode\u003enc.impl.pub.filesystem.FileManageServlet\u003c/code\u003e fails to validate the request body.\u003c/li\u003e\n\u003cli\u003eThe \u003ccode\u003eObjectInputStream.readObject()\u003c/code\u003e method deserializes the untrusted payload.\u003c/li\u003e\n\u003cli\u003eThe deserialization process executes the embedded malicious command on the underlying host OS.\u003c/li\u003e\n\u003cli\u003eAttacker gains remote code execution, typically used for establishing persistence or further lateral movement.\u003c/li\u003e\n\u003c/ol\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eSuccessful exploitation of CVE-2023-54398 results in full, unauthenticated remote code execution on the underlying host running Yonyou U8 Cloud. Attackers can leverage this access to steal sensitive organizational data, manipulate financial information within the ERP, install persistent backdoors, or pivot deeper into the corporate network. Given the critical nature of ERP systems, the impact of such a compromise is high, potentially leading to widespread operational disruption and financial loss.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003col\u003e\n\u003cli\u003ePatch all Yonyou U8 Cloud deployments to the version provided by the vendor that addresses CVE-2023-54398.\u003c/li\u003e\n\u003cli\u003eDeploy the provided webserver detection rule to identify and block incoming HTTP requests containing patterns indicative of Java object serialization.\u003c/li\u003e\n\u003cli\u003eMonitor webserver logs for high-frequency or anomalous POST requests directed at the \u003ccode\u003eFileManageServlet\u003c/code\u003e endpoint.\u003c/li\u003e\n\u003cli\u003eRestrict network access to Yonyou U8 Cloud instances to only essential internal IP ranges, removing exposure from the public internet.\u003c/li\u003e\n\u003c/ol\u003e\n","date_modified":"2026-09-15T17:42:00Z","date_published":"2026-09-15T17:42:00Z","id":"https://feed.craftedsignal.io/briefs/2026-09-cve-2023-54398/","summary":"Yonyou U8 Cloud contains an unauthenticated Java deserialization vulnerability (CVE-2023-54398) in the FileManageServlet component, enabling remote attackers to achieve arbitrary OS command execution.","title":"Unauthenticated RCE in Yonyou U8 Cloud via Java Deserialization","url":"https://feed.craftedsignal.io/briefs/2026-09-cve-2023-54398/"}],"language":"en","title":"CraftedSignal Threat Feed - U8 Cloud","version":"https://jsonfeed.org/version/1.1"}