CVE-2019-25282: V-SOL OLT Platform Open Redirect Flaw

CVE-2019-25282 Overview

CVE-2019-25282 is an open redirect vulnerability affecting V-SOL GPON/EPON OLT Platform v2.03. The vulnerability exists in a script that improperly validates the parent GET parameter, allowing attackers to craft malicious links that redirect authenticated users to arbitrary external websites. This type of vulnerability is commonly exploited in phishing campaigns and credential harvesting attacks targeting network administrators.

Critical Impact

Attackers can exploit this vulnerability to redirect logged-in users to malicious websites, potentially facilitating phishing attacks, credential theft, or malware distribution targeting network infrastructure administrators.

Affected Products

• V-SOL GPON/EPON OLT Platform v2.03
• V-SOL OLT Management Interface (web-based)
• Network devices running vulnerable V-SOL firmware

Discovery Timeline

• 2026-01-08 - CVE-2019-25282 published to NVD
• 2026-01-08 - Last updated in NVD database

Technical Details for CVE-2019-25282

Vulnerability Analysis

This open redirect vulnerability (CWE-601) stems from insufficient input validation in the V-SOL GPON/EPON OLT Platform's web management interface. The affected script accepts a parent GET parameter that controls redirect behavior after certain operations. Because the application fails to properly validate whether the redirect destination is within the trusted domain, attackers can manipulate this parameter to redirect users to arbitrary external URLs.

Open redirect vulnerabilities are particularly dangerous in network management platforms like OLT (Optical Line Terminal) systems because they typically serve as critical infrastructure components. Network administrators who fall victim to such attacks may unknowingly expose credentials or download malware, potentially compromising the entire network infrastructure.

Root Cause

The root cause is improper input validation in the redirect mechanism. The application accepts user-controlled input in the parent parameter without verifying that the target URL belongs to the same application domain or an allowed whitelist of trusted destinations. This violates secure coding practices that require validation of all redirect destinations against a known-safe list of URLs.

Attack Vector

The attack vector is network-based and requires user interaction. An attacker would craft a malicious URL containing the vulnerable endpoint with a manipulated parent parameter pointing to an attacker-controlled website. The crafted link would be distributed through phishing emails, social engineering, or compromised web pages targeting network administrators. When a logged-in user clicks the malicious link, they are seamlessly redirected to the attacker's site, which may mimic a legitimate login page to harvest credentials or serve malicious payloads.

The exploitation path involves:

1. Attacker identifies the vulnerable redirect endpoint in the OLT management interface
2. Attacker crafts a URL with the parent parameter set to a malicious domain
3. The malicious link is sent to targeted network administrators
4. When clicked by an authenticated user, the application redirects to the attacker-controlled site
5. The attacker's site can then phish for credentials or deliver malware

For technical details on the vulnerability mechanism, refer to the Zero Science Vulnerability Report or the Packet Storm Security File.

Detection Methods for CVE-2019-25282

Indicators of Compromise

• HTTP requests to the OLT management interface containing the parent parameter with external URLs
• Unusual redirect patterns in web server access logs originating from the management interface
• Network traffic showing connections to unknown external domains immediately following OLT interface access

Detection Strategies

• Monitor web server logs for requests containing suspicious parent parameter values with external domain references
• Implement URL inspection rules to detect open redirect attempts targeting the OLT management interface
• Deploy web application firewall rules to flag requests with redirect parameters containing non-whitelisted domains
• Review network traffic for anomalous redirect chains originating from the OLT management platform

Monitoring Recommendations

• Enable detailed logging on the V-SOL OLT Platform web interface and centralize logs for analysis
• Configure alerts for any HTTP 302/301 redirects to external domains from the management interface
• Implement network segmentation monitoring to detect unexpected outbound connections from management networks

How to Mitigate CVE-2019-25282

Immediate Actions Required

• Restrict access to the V-SOL GPON/EPON OLT Platform management interface to trusted IP addresses only
• Implement network-level access controls to limit who can reach the management interface
• Educate network administrators about phishing risks and the importance of verifying URLs before clicking
• Consider placing the OLT management interface behind a VPN or bastion host

Patch Information

No vendor patch information is currently available for this vulnerability. Organizations should contact V-SOL directly through their official website to inquire about firmware updates that address this security issue. In the absence of an official patch, implementing the workarounds and access restrictions described below is essential.

Additional technical details can be found in the CXSecurity Vulnerability Report and IBM X-Force Vulnerability Listing.

Workarounds

• Implement a reverse proxy or web application firewall in front of the OLT management interface to validate and sanitize redirect parameters
• Configure firewall rules to block outbound HTTP redirects from the management interface to non-whitelisted domains
• Enable strict content security policies where possible to limit redirect destinations
• Limit management interface access to internal networks only and require VPN for remote administration

# Example: iptables rules to restrict OLT management access to trusted IP ranges
# Adjust IP addresses and ports according to your environment

# Allow management access only from trusted admin subnet
iptables -A INPUT -p tcp --dport 80 -s 10.0.0.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -s 10.0.0.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 80 -j DROP
iptables -A INPUT -p tcp --dport 443 -j DROP