CVE-2020-27576: 
Rumpus vulnerability analysis and mitigation

CVE-2020-27576 affects Maxum Rumpus versions 8.2.13 and 8.2.14. The vulnerability is a stored cross-site scripting (XSS) issue that occurs when users create folders in the web application. The folder name is insufficiently validated, allowing attackers to inject malicious scripts that are stored and executed in the web application context (Advisory, NVD).

The vulnerability exists due to insufficient validation of folder names in the web application. When creating folders, attackers can escape the folder name field and insert HTML including malicious JavaScript. The vulnerability can be triggered by sending a specially crafted POST request to /Rumpus.makefolder with a malicious payload in the FolderName parameter. The CVSS v3.1 base score is 5.4 (Medium) with vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N (NVD, Advisory).

When successfully exploited, the vulnerability allows attackers to inject and store malicious JavaScript code that executes in users' browsers when they view the affected folders. This can lead to theft of session cookies, credentials, and other sensitive information from users who view the compromised folders (Advisory).

The vulnerability requires authentication to create folders, but once exploited, the stored XSS payload affects all users who view the compromised folder names. When combined with other vulnerabilities (CVE-2020-27574 and CVE-2020-27575), it can be leveraged to achieve remote code execution with root privileges (Advisory).

No official patch is available for this vulnerability. The main mitigation is to disable remote user management functionality in the application to reduce the attack surface. Organizations should also implement proper input validation and output encoding for folder names (Advisory).