CVE-2025-66620
HighCVSS 8.0Exploitation Probability (EPSS)
Low risk16th percentile - higher than 16% of all known CVEs
Summary
An unused webshell in MicroServer allows unlimited login attempts, with sudo rights on certain files and directories. An attacker with admin access to MicroServer can gain limited shell access, enabling persistence through reverse shells, and the ability to modify or remove data stored in the file system.
Risk Assessment
An attacker can gain persistent access to the system, potentially leading to confidentiality, integrity, and availability breaches.
Recommendation
Remove or disable the unused webshell and restrict administrative access to MicroServer.
Other vulnerabilities in MicroServer
See all- CVE-2025-64305Medium
MicroServer copies parts of the system firmware to an unencrypted external SD card on boot, which contains user and vendor secrets. An attacker can utilize these plaintext secrets to modify the vendor firmware, or gain admin access to the web portal.
- CVE-2025-61939High
An unused function in MicroServer can start a reverse SSH connection to a vendor registered domain, without mutual authentication. An attacker on the local network with admin access to the web server, and the ability to manipulate DNS responses, can redirect the SSH connection to an attacker controlled device.
Original NVD description (English source)
An unused webshell in MicroServer allows unlimited login attempts, with sudo rights on certain files and directories. An attacker with admin access to MicroServer can gain limited shell access, enabling persistence through reverse shells, and the ability to modify or remove data stored in the file system.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS