CVE-2025-61939
HighCVSS 8.8Exploitation Probability (EPSS)
Low risk29th percentile - higher than 29% of all known CVEs
Summary
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.
Risk Assessment
An attacker can intercept the SSH connection and gain unauthorized access to the system, potentially leading to security breaches.
Recommendation
Disable the unused function and ensure mutual authentication for SSH connections.
Other vulnerabilities in MicroServer
See all- CVE-2025-66620High
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.
- 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.
Original NVD description (English source)
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.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS