CVE-2019-25478: GetGo Download Manager DoS Vulnerability

CVE-2019-25478 Overview

GetGo Download Manager version 6.2.2.3300 contains a buffer overflow vulnerability (CWE-787: Out-of-Bounds Write) that enables remote attackers to cause denial of service conditions. The vulnerability occurs when the application processes HTTP responses containing excessively long header values. Attackers can craft malicious HTTP responses with oversized headers to crash the application, rendering it unavailable to legitimate users.

Critical Impact

Remote attackers can exploit this buffer overflow via network-based attacks without authentication to crash GetGo Download Manager, causing complete loss of availability for affected systems.

Affected Products

• GetGo Download Manager 6.2.2.3300

Discovery Timeline

• 2026-03-11 - CVE-2019-25478 published to NVD
• 2026-03-12 - Last updated in NVD database

Technical Details for CVE-2019-25478

Vulnerability Analysis

This buffer overflow vulnerability exists in how GetGo Download Manager processes incoming HTTP response headers. The application fails to properly validate the length of header values before copying them into fixed-size memory buffers. When a malicious server or man-in-the-middle attacker sends an HTTP response with header values exceeding the expected buffer size, the excess data overflows into adjacent memory regions.

The vulnerability is classified as CWE-787 (Out-of-Bounds Write), indicating that the application writes data past the boundaries of allocated memory. This type of memory corruption vulnerability can cause immediate application crashes, resulting in denial of service. The network-based attack vector means exploitation can occur remotely without requiring any user interaction or authentication.

Root Cause

The root cause lies in insufficient bounds checking within the HTTP response header parsing routines of GetGo Download Manager. When processing HTTP headers, the application allocates a fixed-size buffer to store header values but does not verify that incoming header data fits within these bounds before performing memory write operations. This allows attackers to trigger out-of-bounds writes by sending headers that exceed buffer capacity.

Attack Vector

The attack leverages the network-based HTTP communication that GetGo Download Manager uses to fetch files. An attacker can exploit this vulnerability through several methods:

1. Malicious Server: Setting up a malicious HTTP server that responds with oversized headers when the victim attempts to download a file
2. Man-in-the-Middle: Intercepting legitimate HTTP responses and injecting oversized header values
3. DNS Hijacking: Redirecting download requests to attacker-controlled servers that serve malicious responses

The exploitation requires no authentication and no user interaction beyond initiating a download request. When the application attempts to parse the malicious HTTP response, the buffer overflow occurs, causing the application to crash. Additional technical details can be found in the Exploit-DB #47282 entry and the Vulncheck Advisory for GetGo.

Detection Methods for CVE-2019-25478

Indicators of Compromise

• Unexpected crashes or termination of GetGo Download Manager processes
• Abnormally large HTTP response headers in network traffic logs (header values exceeding typical sizes)
• Network connections to unfamiliar or suspicious download servers
• Application error logs showing memory access violations or buffer-related exceptions

Detection Strategies

• Monitor network traffic for HTTP responses with unusually large header values targeting download manager applications
• Implement application crash monitoring to detect repeated GetGo Download Manager failures
• Deploy network intrusion detection rules to identify HTTP responses with excessively long headers
• Review DNS logs for unexpected redirections of download URLs to unknown servers

Monitoring Recommendations

• Configure endpoint detection and response (EDR) solutions to alert on GetGo Download Manager process crashes
• Enable verbose logging for download manager activities to capture HTTP response details
• Monitor for patterns of repeated application restarts that may indicate ongoing exploitation attempts
• Implement network traffic analysis to baseline normal HTTP header sizes and alert on anomalies

How to Mitigate CVE-2019-25478

Immediate Actions Required

• Consider discontinuing use of GetGo Download Manager 6.2.2.3300 until a patched version is available
• Use alternative download manager applications that do not have known buffer overflow vulnerabilities
• Restrict downloads to trusted HTTPS sources to reduce man-in-the-middle attack risk
• Implement network-level controls to block or inspect HTTP traffic for oversized headers

Patch Information

No official patch information is available from the vendor at this time. Users should check the GetGoSoft Product Page for potential updates. Given the age of this vulnerability (CVE from 2019), the product may no longer be actively maintained. Organizations should evaluate whether continued use of this software is appropriate given the security risk.

Workarounds

• Use HTTPS-only download sources to reduce the attack surface for man-in-the-middle exploitation
• Deploy network security appliances capable of inspecting and limiting HTTP header sizes
• Consider application sandboxing or containerization to limit the impact of potential crashes
• Migrate to actively maintained download manager alternatives with better security track records

# Network-level mitigation: Example iptables rule to limit packet sizes (adjust as needed)
# This is a general mitigation approach, not specific to this vulnerability
iptables -A INPUT -p tcp --dport 80 -m length --length 8192:65535 -j DROP