Overview
CVE-2025-25613 details a critical security vulnerability found in FS Inc’s S3150-8T2F 8-Port Gigabit Ethernet L2+ Switch. Specifically, versions prior to 2.2.0D Build 135103 transmit cookies containing administrative usernames and passwords in cleartext. This occurs during every POST request made to the web-based administrative application, using a simple Base64 encoding, effectively making the credentials easily retrievable by attackers.
Technical Details
The vulnerability stems from the switch’s web interface failing to properly encrypt or hash user credentials. Instead, the username and password are encoded using Base64 before being transmitted as part of the cookie during POST requests. Base64 is an encoding scheme, not encryption, and can be easily decoded to reveal the original credentials. An attacker intercepting network traffic (e.g., through man-in-the-middle attacks or network sniffing) can capture these cookies and decode the credentials to gain administrative access to the switch.
The core issue lies in the lack of secure communication protocols (e.g., HTTPS) and secure credential storage/transmission mechanisms.
CVSS Analysis
Currently, the CVE entry lists the CVSS score as N/A. However, given the nature of the vulnerability (cleartext transmission of administrative credentials), a high CVSS score is anticipated upon assignment. A likely score would fall within the 8.0-10.0 range, classifying it as High or Critical, depending on factors such as exploitability and scope of impact. The primary attack vector is likely network-based, requiring an attacker to be positioned to intercept network traffic.
Possible Impact
The exploitation of CVE-2025-25613 can have severe consequences, including:
- Full Administrative Control: An attacker can gain complete control over the affected switch.
- Network Disruption: The attacker can reconfigure the switch, causing network outages, denial-of-service conditions, or redirect traffic.
- Data Exfiltration: The attacker can use the compromised switch as a pivot point to access other devices on the network and potentially exfiltrate sensitive data.
- Malware Deployment: The attacker can deploy malware to the switch or other devices on the network.
- Lateral Movement: The compromised switch could be used as a stepping stone to compromise other systems within the network.
Mitigation and Patch Steps
The primary mitigation step is to upgrade the switch firmware to version 2.2.0D Build 135103 or later. This version contains a patch that addresses the vulnerability.
In the interim, consider the following steps to reduce the risk:
- Isolate the Switch: Place the switch on a dedicated VLAN with limited access.
- Monitor Network Traffic: Implement network monitoring tools to detect suspicious activity.
- Change Default Credentials: If possible (pending the firmware update), change the default administrator credentials to strong, unique passwords. However, be aware that this will still be transmitted in Base64 until the patch is applied.
- Implement Network Segmentation: Segment the network to limit the potential impact of a compromise.
