H3C CVM Unauthenticated File Upload via fileUpload/upload Token

H3C CVM, the Cloud Virtualization Management component of the H3C CAS cloud platform, contains an unauthenticated arbitrary file upload vulnerability in the /cas/fileUpload/upload endpoint that allows remote attackers to write arbitrary files by manipulating the caller-supplied token parameter without restricting path traversal or file type. Attackers can exploit the path traversal in the token parameter to upload a malicious JSP file into a web-accessible directory and then request it to achieve remote code execution as the web-server user. Exploitation evidence was first observed by the Shadowserver Foundation on 2023-10-14.